Replaces the synchronous `requests.post` and `requests.get` calls in
`app/api/onedrive.py:test_onedrive_token` with an asynchronous
`httpx.AsyncClient` implementation. This unblocks the FastAPI event loop
when this endpoint is hit.
Tests were updated to mock `httpx.AsyncClient` and a sync wrapper using `asyncio.run` was added to integration tests to maintain test coverage without massive test refactoring.
Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>