Bugfix/DEV 11349 fix unlinked awards lasya

[LKambhampati-frb]

Description: Fixed Unlinked Awards API endpoint - was returning URL with repeated fields causing issues downloading requested data for users

Technical details: _latest_download_filename repeated the _self.redirectdir variable, which was already added to the URL returned by the endpoint in the _identifieddownload. Removing the duplicate solved the issue.

Requirements for PR merge:

1. [x] Unit & integration tests updated
2. [ ] API documentation updated (N/A)
3. [ ] Necessary PR reviewers:
   • [x] Backend
   • [x] Frontend
   • [ ] Operations
   • [ ] Domain Expert
4. [ ] Matview impact assessment completed (N/A)
5. [ ] Frontend impact assessment completed (N/A)
6. [ ] Data validation completed
7. [ ] Appropriate Operations ticket(s) created
8. [ ] Jira Ticket DEV-123:
   • [ ] Link to this Pull-Request
   • [ ] Performance evaluation of affected (API | Script | Download)
   • [ ] Before / After data comparison

Area for explaining above N/A when needed:

API endpoint definition was not modified. 

[ghost]

We talked about this PR, good job.