[3.14] gh-135871: Fix needless spinning in `_PyMutex_LockTimed` with zero timeout (gh-135872) (gh-135946)

The free threading build could spin unnecessarily on `_Py_yield()` if the initial
compare and swap failed.
(cherry picked from commit cbfaf41caf135b8598a560854cd59e992a2ccfed)

Co-authored-by: Joseph Tibbertsma <josephtibbertsma@gmail.com>