Issue:
bug(events): update the ApiEventsType for `PaymentsSessionResponse` to use payments flow

update the `ApiEventMetric` trait for this response to return `ApiEventsType::Payment { payment_id : String}` variant.
based on the payment id stored in its body

This would help for better structuring and help list this api call in the dashboard events as well

Resolution:
<think>
PR Context:
- Title: fix(event): Updated the ApiEventMetric
- Merged: 2024-07-02T15:18:04Z
- Files changed: 2 files
- Commits: 13 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [x] Bugfix


## Description
<!-- Describe your changes in detail -->
Updated the `ApiEventMetric` trait to return `ApiEventsType::Payment { payment_id : String}` variant.
Fixes #5059 



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## Checklist
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</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** fix(event): Updated the ApiEventMetric (#5126)
Co-authored-by: Sampras Lopes <Sampras.lopes@juspay.i
Files to modify:


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

**crates/api_models/src/events/payment.rs**
  Add:
    - function: private::get_api_event_type
    - impl: impl ApiEventMetric for PaymentsSessionResponse