Issue:
[REFACTOR] API Key List and Update endpoints in Hyperswitch V2

Update API Key endpoint in V2, the URLs are registered in the `app.rs` but the necessary changes to it has not been made in `api_keys.rs`.

In addition to that, List API Key endpoint for V2 does not work as no such thing exist in `api_keys.rs`.

So at present, when that endpoint is hit, you'll receive a 404 as mentioned below:

```curl
curl --location --request PUT '{{baseUrl}}/v2/api_keys/{{api_key_id}}' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--header 'x-merchant-id: {{mechant_id}}' \
--header 'api-key: {{admin_api_key}}' \
--data '{
     "name": "My new Api Key"
}'
```
```json
wrong number of parameters: 1 expected 2
```

List end point:

```curl
curl --location '{{baseUrl}}/v2/api_keys/list' \
--header 'x-merchant-id: {{mechant_id}}' \
--header 'api-key: {{admin_api_key}}'
```
```json
wrong number of parameters: 0 expected 1
```

I'll be fixing this.

Resolution:
<think>
PR Context:
- Title: fix(api_key): fix api key `list` and `update` endpoints for v2
- Merged: 2024-09-25T11:17:57Z
- Files changed: 12 files
- Commits: 13 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [x] Bugfix
- [ ] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->

This PR fixes `404` errors thrown by API Key List and Update endpoints.

Previously:

Update end point:

```curl
curl --location --request PUT '{{baseUrl}}/v2/api_keys/{{api_key_id}}' \
--header 'Content-Type: application/json' \
--
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** fix(api_key): fix api key `list` and `update` endpoints for v2 (#5980)
Files to modify:


**crates/api_models/src/api_keys.rs**
  Modify existing code

**crates/api_models/src/events.rs**
  Modify existing code

**crates/openapi/src/openapi.rs**
  Modify existing code

**crates/openapi/src/openapi_v2.rs**
  Modify existing code

**crates/openapi/src/routes/api_keys.rs**
  Add:
    - function: pub::api_key_list
    - function: pub::api_key_list

**crates/router/src/routes/api_keys.rs**
  Modify existing code