test : add unit tests for fetchUserRepos function

[tmdeveloper007]

Summary of What Needs to be Done:
Add unit tests for the fetchUserRepos function in src/lib/github.ts. Tests must use vitest framework and import actual source code.

Changes that Need to be Made:

• Create test using vitest describe/it/expect
• Import fetchUserRepos from src/lib/github.ts
• Test makes correct API call with auth header
• Test throws error on non-ok response
• Test constructs correct endpoint

Impact that it would Provide:

• Ensures GitHub API calls are correctly formed
• Validates error handling for API failures

[Harsh-Codes-77]

/assign

[github-actions]

✅ Closed as completed!

If DevTrack has been useful, a ⭐ star on the repo helps the project grow and reach more developers.