feat: delete with provider validation

[nsprenkle]

Adds an optional provider param for the video-transcript DELETE endpoint for additional validation.

DELETE /val/v0/videos/video-transcripts?video_id={video_id}&language_code={language_code}&provider={provider} /HTTP/1.1

For backwards compatibility, this is optional: where omitted, the delete endpoint operates as previously defined and, whether found or not, returns a 204.

HTTP/1.1 204 No Content

Where provided (pun intended), the provider param checks that the given provider matches that of the identified transcript, failing with a 404.

HTTP/1.1 404 Not Found
Content-Type: application/json

{
    "message": "Transcript provider does not match, cannot delete the transcript."
}

[Copilot]

Pull Request Overview

This PR adds optional provider validation to the video-transcript DELETE endpoint. When a provider parameter is supplied, the endpoint validates that it matches the existing transcript's provider before deletion, returning a 404 error if there's a mismatch.

• Added optional provider query parameter to the DELETE endpoint for additional validation
• Created new TranscriptNotFoundError exception for provider mismatch scenarios
• Updated the delete_video_transcript API function to accept and validate the provider parameter

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
edxval/views.py	Added provider parameter extraction and TranscriptNotFoundError handling in DELETE endpoint
edxval/api.py	Enhanced delete_video_transcript function with optional provider validation logic
edxval/exceptions.py	Introduced new TranscriptNotFoundError exception class
edxval/tests/test_views.py	Added test cases for provider validation scenarios and updated existing tests

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.84%. Comparing base (a46f718) to head (51577e4).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #592      +/-   ##
==========================================
+ Coverage   94.81%   94.84%   +0.03%     
==========================================
  Files          33       33              
  Lines        3315     3337      +22     
  Branches      127      128       +1     
==========================================
+ Hits         3143     3165      +22     
  Misses        154      154              
  Partials       18       18              

Flag	Coverage Δ
unittests	94.84% <100.00%> (+0.03%)	⬆️

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[michaelroytman]

Looks good to me!