Issue:
Bug:  [FEATURE] : [Fiserv] mask pii information in connector request and response



### Feature Description

Mask pii information passed and received in the connector request and response

### Possible Implementation

Refactor all sensitive response and request fields secret

### Have you spent some time checking if this feature request 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 -->

- [ ] Bugfix
- [ ] New feature
- [x] Enhancement
- [x] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->
Mask pii information passed and received in the connector request and response for Fiserv.


## Test case
1. Create a card payment with fiserv
```
curl --location 'http://localhost:8080/payments' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--header 'api-key:{{api_key}}' \
--data-raw '{
    "amount": 2000,
    "currency": "USD",
    "confirm": true,
    "capture_method": "automatic",
    "capture_on": "2022-09-10T10:11:12Z",
    "customer_id": "StripeCustomer",
    "email": "abcdef123@gmail.com",
    "name": "John Doe",
    "phone": "999999999",
    "phone_country_code": "+65",
    "description": "Its my first payment request",
    "authentication_type": "no_three_ds",
    "return_url": "https://google.com",
    
    "billing": {
        "address": {
            "line1": "1467",
            "line2": "Harrison Street",
            "line3": "Harrison Street",
            "city": "San Fransico",
            "state": "California",
            "zip": "94122",
            "country": "US",
            "first_name": "John",
            "last_name": "Doe"
        }
    },
    "browser_info": {
        "user_agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36",
        "accept_header": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8",
        "language": "nl-NL",
        "color_depth": 24,
        "screen_height": 723,
        "screen_width": 1536,
        "time_zone": 0,
        "java_enabled": true,
        "java_script_enabled": true,
        "ip_address": "127.0.0.1"
    },
    "shipping": {
        "address": {
            "line1": "1467",
            "line2": "Harrison Street",
            "line3": "Harrison Street",
            "city": "San Fransico",
            "state": "California",
            "zip": "94122",
            "country": "US",
            "first_name": "John",
            "last_name": "Doe"
        }
    },
    "statement_descriptor_name": "joseph",
    "statement_descriptor_suffix": "JS",
    "metadata": {
        "udf1": "value1",
        "new_customer": "true",
        "login_date": "2019-09-10T10:11:12Z"
    },
    "payment_method": "card",
    "payment_method_data": {
        "card": {
            "card_number": "4111111111111111",
            "card_exp_month": "10",
            "card_exp_year": "30",
            "card_holder_name": "Joseph Doe",
            "card_cvc": "123"
        }
    }
}'
```

1.b. Check if all the sensitive data in the `masked_response` and also in `request` is masked

```
curl --location '{{base_url}}/analytics/v1/connector_event_logs?type=Payment&payment_id={{payment_id}}' \
--header 'sec-ch-ua: "Not A(Brand";v="99", "Google Chrome";v="121", "Chromium";v="121"' \
--header 'sec-ch-ua-mobile: ?0' \
--header 'authorization: Bearer JWT_token' \
--header 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36' \
--header 'Content-Type: application/json' \
--header 'Referer: https://integ.hyperswitch.io/' \
--header 'api-key: {{api-key}}' \
--header 'sec-ch-ua-platform: "macOS"'
```

Masked Request
```
request\":\"{\\\"amount\\\":{\\\"total\\\":20.0,\\\"currency\\\":\\\"USD\\\"},\\\"source\\\":{\\\"sourceType\\\":\\\"PaymentCard\\\",\\\"card\\\":{\\\"cardData\\\":\\\"411111**********\\\",\\\"expirationMonth\\\":\\\"*** alloc::string::String ***\\\",\\\"expirationYear\\\":\\\"*** alloc::string::String ***\\\",\\\"securityCode\\\":\\\"*** alloc::string::String ***\\\"}},\\\"transactionDetails\\\":{\\\"captureFlag\\\":true,\\\"reversalReasonCode\\\":null,\\\"merchantTransactionId\\\":\\\"pay_IRGqmgQ7FkrCPXxyCWfa_1\\\"},\\\"merchantDetails\\\":{\\\"merchantId\\\":\\\"*** alloc::string::String ***\\\",\\\"terminalId\\\":\\\"*** alloc::string::String ***\\\"},\\\"transactionInteraction\\\":{\\\"origin\\\":\\\"ECOM\\\",\\\"eciIndicator\\\":\\\"CHANNEL_ENCRYPTED\\\",\\\"posConditionCode\\\":\\\"CARD_NOT_PRESENT_ECOM\\\"}}
```

Masked Response
```
"masked_response\":\"{\\\"gatewayResponse\\\":{\\\"gatewayTransactionId\\\":null,\\\"transactionState\\\":\\\"CAPTURED\\\",\\\"transactionProcessingDetails\\\":{\\\"orderId\\\":\\\"CHG01a86281900c326c5f580655313a9cc7cb\\\",\\\"transactionId\\\":\\\"4a695b8bd77b448d80ebb13640561fe7\\\"}}}
```

## Impacted Area
> Payment Create flow 

## 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:

Patch:
diff --git a/crates/router/src/connector/fiserv/transformers.rs b/crates/router/src/connector/fiserv/transformers.rs
index e2511dc8d56..b8dd3c9643f 100644
--- a/crates/router/src/connector/fiserv/transformers.rs
+++ b/crates/router/src/connector/fiserv/transformers.rs
@@ -62,8 +62,8 @@ pub enum Source {
     },
     #[allow(dead_code)]
     GooglePay {
-        data: String,
-        signature: String,
+        data: Secret<String>,
+        signature: Secret<String>,
         version: String,
     },
 }
@@ -80,8 +80,8 @@ pub struct CardData {
 #[derive(Default, Debug, Serialize)]
 #[serde(rename_all = "camelCase")]
 pub struct GooglePayToken {
-    signature: String,
-    signed_message: String,
+    signature: Secret<String>,
+    signed_message: Secret<String>,
     protocol_version: String,
 }
 
@@ -104,7 +104,7 @@ pub struct TransactionDetails {
 #[serde(rename_all = "camelCase")]
 pub struct MerchantDetails {
     merchant_id: Secret<String>,
-    terminal_id: Option<String>,
+    terminal_id: Option<Secret<String>>,
 }
 
 #[derive(Default, Debug, Serialize)]
@@ -428,7 +428,7 @@ pub struct ReferenceTransactionDetails {
 
 #[derive(Debug, Default, Serialize, Deserialize)]
 pub struct FiservSessionObject {
-    pub terminal_id: String,
+    pub terminal_id: Secret<String>,
 }
 
 impl TryFrom<&Option<pii::SecretSerdeValue>> for FiservSessionObject {