bpo-45997: Fix asyncio.Semaphore waiters order

[hyzyla]

Allow other Semaphore waiters to acquire lock after releasing by current coroutine by skipping one event loop iteration. If everything is OK for Semaphore, I can add the same logic to other asyncio synchronization primitives

https://bugs.python.org/issue45997

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[asvetlov]

The PR adds unconditional sleep even if the waiting is not needed (the context was switched already).
I think we need an alternative implementation based on future object waiting.

[bedevere-bot]

A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated.

Once you have made the requested changes, please leave a comment on this pull request containing the phrase I have made the requested changes; please review again. I will then notify any core developers who have left a review that you're ready for them to take another look at this pull request.

[github-actions]

This PR is stale because it has been open for 30 days with no activity.

[taleinat]

@hyzyla, are you interested in continuing to work on this PR following @asvetlov's comment?

(If so, you will need to to sign the CLA.)

[hyzyla]

I would like to return to PR in few weeks, I have idea where I will create Future, then will put it to loop via call_soon and in the end in acquire method waiting for that Future

[taleinat]

Alright @hyzyla, looking forward to what you'll come up with!

[asvetlov]

#31910 is an alternative fix

[asvetlov]

Thanks for the PR!
Fixed by #31910