feat(router): add delete_evidence api for disputes

[sai-harsha-vardhan]

Type of Change

• Bugfix
• New feature
• Enhancement
• Refactoring
• Dependency updates
• Documentation
• CI/CD

Description

add delete_evidence api for disputes

Additional Changes

• This PR modifies the API contract
• This PR modifies the database schema
• This PR modifies application configuration/environment variables

Motivation and Context

How did you test it?

Tested Manually

1. Create a dispute through checkout connector with dispute_opened status (docs)

2. Add multiple evidences to the dispute using attach_evidence API
   
   

3. Check dispute record in DB for entries (Alternatively can call retrieve_evidence API)
   

4. Call the delete_evidence API to delete a particular evidence type for a dispute
   

5. Check in DB if that evidence type is deleted and others are not changed (Alternatively can call retrieve_evidence API)
   

Checklist

• I formatted the code cargo +nightly fmt --all
• I addressed lints thrown by cargo clippy
• I reviewed the submitted code
• I added unit tests for my changes where possible
• I added a CHANGELOG entry if applicable

[Narayanbhat166]

are we not deleting the evidence file from the source?

[sai-harsha-vardhan]

are we not deleting the evidence file from the source?

@Narayanbhat166 There are no Delete File APIs with connectors (stripe, checkout etc.). So, we are just deleting the mapping, and while submitting evidence we send only which are not deleted.