Issue:
Bug: [BUG] : [Adyen] Production URL endpoint



### Bug Description

For Adyen production URL endpoint is not correctly configured as compared to how it is used

### Expected Behavior

`/` is missing in the end for production endpoint

### Actual Behavior

For Adyen production URL endpoint is not correctly configured as compared to how it is used

### Steps To Reproduce

Provide an unambiguous set of steps to reproduce this bug. Include code or configuration to reproduce, if relevant.
1. Go to '...'
2. Click on '....'
3. Scroll down to '....'


### Context For The Bug

_No response_

### Environment

Are you using hyperswitch hosted version? Yes/No
If yes, please provide the value of the `x-request-id` response header to help us debug your issue.

If not (or if building/running locally), please provide the following details:
1. Operating System or Linux distribution:
2. Rust version (output of `rustc --version`): ``
3. App version (output of `cargo r --features vergen -- --version`): ``


### Have you spent some time checking if this bug has been raised before?

- [X] I checked and didn't find a similar issue

### Have you read the Contributing Guidelines?

- [X] I have read the [Contributing Guidelines](https://github.com/juspay/hyperswitch/blob/main/docs/CONTRIBUTING.md)

### Are you willing to submit a PR?

Yes, I am willing to submit a PR!

Pull request description:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [X] Bugfix
- [ ] New feature
- [X] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->

- Update Prod URL endpoint
- Handle refunds webhooks using hyperswitch internal refund id
- Add card holder name

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [X] This PR modifies application configuration/environment variables

<!--
Provide links to the files with corresponding changes.

Following are the paths where you can find config files:
1. `config`
2. `crates/router/src/configs`
3. `loadtest/config`
-->
Updated Prod URL endpoint

## Motivation and Context
<!--
Why is this change required? What problem does it solve?
If it fixes an open issue, please link to the issue here.

If you don't have an issue, we'd recommend starting with one first so the PR
can focus on the implementation (unless it is an obvious bug or documentation fix
that will have little conversation).
-->
#4047 

## How did you test it?
<!--
Did you write an integration/unit/API test to verify the code changes?
Or did you test this change manually (provide relevant screenshots)?
-->
- Trigger a refunds transaction
```
curl --location 'http://localhost:8080/refunds' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--header 'api-key: dev_gwfA0IT4jpKdcUSmJlWMJ0jawjc5ziP6lA91du0gpc9ydEzI5HajDN18Wr72NkS7' \
--data '{
    "payment_id": "pay_ow2YSNvgVDZlGTv3o8wc",
    
    "reason": "RETURN",
    "refund_type": "instant",
    "metadata": {
        "udf1": "value1",
        "new_customer": "true",
        "login_date": "2019-09-10T10:11:12Z"
    }
}'
```
- Check for outgoing webhook and also retrieve the refund to confirm the Status change
![Screenshot 2024-03-12 at 6 31 39 PM](https://github.com/juspay/hyperswitch/assets/55536657/b6195d05-7972-4079-b1f6-bdeee1fb1f2f)


- Send card holder name in the cards request it should be visible in Adyen Dashboard for the payment
```
curl --location 'http://localhost:8080/payments' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--header 'api-key: dev_gwfA0IT4jpKdcUSmJlWMJ0jawjc5ziP6lA91du0gpc9ydEzI5HajDN18Wr72NkS7' \
--data-raw '{
    "amount": 6540,
    "currency": "EUR",
    "confirm": true,
    "capture_method": "automatic",
    "capture_on": "2022-09-10T10:11:12Z",
    "amount_to_capture": 6540,
    "customer_id": "StripeCustomer",
    "email": "guest@example.com",
    "name": "John Doe",
    "phone": "999999999",
    "phone_country_code": "+1",
    "description": "Its my first payment request",
    "authentication_type": "no_three_ds",
    "return_url": "https://duck.com",
    "profile_id": "pro_8Ix85cVgHD3x4DQIFZTV",
    "business_country": "US",
    "payment_method": "card",
    "payment_method_type": "credit",
    "payment_method_data": {
        "card": {
            "card_number": "371449635398431",
            "card_exp_month": "03",
            "card_exp_year": "2030",
            "card_holder_name": "joseph Doe",
            "card_cvc": "7373"
        }
    },
    "routing": {
        "type": "single",
        "data": "adyen"
    },
    "billing": {
        "address": {
            "line1": "1467",
            "line2": "Harrison Street",
            "line3": "Harrison Street",
            "city": "San Fransico",
            "state": "California",
            "zip": "94122",
            "country": "DE",
            "first_name": "PiX"
        }
    },
    "shipping": {
        "address": {
            "line1": "1467",
            "line2": "Harrison Street",
            "line3": "Harrison Street",
            "city": "San Fransico",
            "state": "California",
            "zip": "94122",
            "country": "US",
            "first_name": "PiX"
        }
    },
    "statement_descriptor_name": "This is me making a statement",
    "statement_descriptor_suffix": "JS",
    "metadata": {
        "udf1": "value1",
        "new_customer": "true",
        "login_date": "2019-09-10T10:11:12Z"
    }
}'
```
## Checklist
<!-- Put an `x` in the boxes that apply -->

- [X] I formatted the code `cargo +nightly fmt --all`
- [X] I addressed lints thrown by `cargo clippy`
- [X] I reviewed the submitted code
- [ ] I added unit tests for my changes where possible
- [ ] I added a [CHANGELOG](/CHANGELOG.md) entry if applicable


Testing:

- Trigger a refunds transaction
```
curl --location 'http://localhost:8080/refunds' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--header 'api-key: dev_gwfA0IT4jpKdcUSmJlWMJ0jawjc5ziP6lA91du0gpc9ydEzI5HajDN18Wr72NkS7' \
--data '{
    "payment_id": "pay_ow2YSNvgVDZlGTv3o8wc",
    
    "reason": "RETURN",
    "refund_type": "instant",
    "metadata": {
        "udf1": "value1",
        "new_customer": "true",
        "login_date": "2019-09-10T10:11:12Z"
    }
}'
```
- Check for outgoing webhook and also retrieve the refund to confirm the Status change
![Screenshot 2024-03-12 at 6 31 39 PM](https://github.com/juspay/hyperswitch/assets/55536657/b6195d05-7972-4079-b1f6-bdeee1fb1f2f)


- Send card holder name in the cards request it should be visible in Adyen Dashboard for the payment
```
curl --location 'http://localhost:8080/payments' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--header 'api-key: dev_gwfA0IT4jpKdcUSmJlWMJ0jawjc5ziP6lA91du0gpc9ydEzI5HajDN18Wr72NkS7' \
--data-raw '{
    "amount": 6540,
    "currency": "EUR",
    "confirm": true,
    "capture_method": "automatic",
    "capture_on": "2022-09-10T10:11:12Z",
    "amount_to_capture": 6540,
    "customer_id": "StripeCustomer",
    "email": "guest@example.com",
    "name": "John Doe",
    "phone": "999999999",
    "phone_country_code": "+1",
    "description": "Its my first payment request",
    "authentication_type": "no_three_ds",
    "return_url": "https://duck.com",
    "profile_id": "pro_8Ix85cVgHD3x4DQIFZTV",
    "business_country": "US",
    "payment_method": "card",
    "payment_method_type": "credit",
    "payment_method_data": {
        "card": {
            "card_number": "371449635398431",
            "card_exp_month": "03",
            "card_exp_year": "2030",
            "card_holder_name": "joseph Doe",
            "card_cvc": "7373"
        }
    },
    "routing": {
        "type": "single",
        "data": "adyen"
    },
    "billing": {
        "address": {
            "line1": "1467",
            "line2": "Harrison Street",
            "line3": "Harrison Street",
            "city": "San Fransico",
            "state": "California",
            "zip": "94122",
            "country": "DE",
            "first_name": "PiX"
        }
    },
    "shipping": {
        "address": {
            "line1": "1467",
            "line2": "Harrison Street",
            "line3": "Harrison Street",
            "city": "San Fransico",
            "state": "California",
            "zip": "94122",
            "country": "US",
            "first_name": "PiX"
        }
    },
    "statement_descriptor_name": "This is me making a statement",
    "statement_descriptor_suffix": "JS",
    "metadata": {
        "udf1": "value1",
        "new_customer": "true",
        "login_date": "2019-09-10T10:11:12Z"
    }
}'
```

Patch:
diff --git a/config/deployments/production.toml b/config/deployments/production.toml
index 892f11e9415..a6a37858308 100644
--- a/config/deployments/production.toml
+++ b/config/deployments/production.toml
@@ -17,7 +17,7 @@ payout_connector_list = "wise"
 
 [connectors]
 aci.base_url = "https://eu-test.oppwa.com/"
-adyen.base_url = "https://{{merchant_endpoint_prefix}}-checkout-live.adyenpayments.com/checkout"
+adyen.base_url = "https://{{merchant_endpoint_prefix}}-checkout-live.adyenpayments.com/checkout/"
 adyen.secondary_base_url = "https://{{merchant_endpoint_prefix}}-pal-live.adyenpayments.com/"
 airwallex.base_url = "https://api-demo.airwallex.com/"
 applepay.base_url = "https://apple-pay-gateway.apple.com/"
diff --git a/crates/router/src/connector/adyen.rs b/crates/router/src/connector/adyen.rs
index 67e319ddc22..d79761da472 100644
--- a/crates/router/src/connector/adyen.rs
+++ b/crates/router/src/connector/adyen.rs
@@ -1761,7 +1761,7 @@ impl api::IncomingWebhook for Adyen {
         }
         if adyen::is_refund_event(&notif.event_code) {
             return Ok(api_models::webhooks::ObjectReferenceId::RefundId(
-                api_models::webhooks::RefundIdType::ConnectorRefundId(notif.psp_reference),
+                api_models::webhooks::RefundIdType::RefundId(notif.merchant_reference),
             ));
         }
         if adyen::is_chargeback_event(&notif.event_code) {
diff --git a/crates/router/src/connector/adyen/transformers.rs b/crates/router/src/connector/adyen/transformers.rs
index 1eede78503b..cff6c7a8d99 100644
--- a/crates/router/src/connector/adyen/transformers.rs
+++ b/crates/router/src/connector/adyen/transformers.rs
@@ -1128,6 +1128,7 @@ pub struct AdyenCard {
     expiry_month: Secret<String>,
     expiry_year: Secret<String>,
     cvc: Option<Secret<String>>,
+    holder_name: Option<Secret<String>>,
     brand: Option<CardBrand>, //Mandatory for mandate using network_txns_id
     network_payment_reference: Option<Secret<String>>,
 }
@@ -1980,6 +1981,7 @@ impl<'a> TryFrom<&api::Card> for AdyenPaymentMethod<'a> {
             expiry_month: card.card_exp_month.clone(),
             expiry_year: card.get_expiry_year_4_digit(),
             cvc: Some(card.card_cvc.clone()),
+            holder_name: card.card_holder_name.clone(),
             brand: None,
             network_payment_reference: None,
         };
@@ -2584,6 +2586,7 @@ impl<'a>
                             expiry_month: card.card_exp_month.clone(),
                             expiry_year: card.card_exp_year.clone(),
                             cvc: None,
+                            holder_name: card.card_holder_name.clone(),
                             brand: Some(brand),
                             network_payment_reference: Some(Secret::new(network_mandate_id)),
                         };