Change PyMutex_LockFast to take mutex as argument

[kumaraditya303]

PyMutex_LockFast is the only function which takes the bits from mutex directly rather than the mutex. It breaks a good abstraction so I propose to change it to take the mutex as its argument like all other functions.

cc @colesbury

Linked PRs

• gh-128033: change PyMutex_LockFast to take PyMutex as argument #128054

[colesbury]

That makes sense to me.