Use asyncio.timeout for Python 3.11+

[cdce8p]

async-timeout is deprecated for Python 3.11+ as it's now included in the stdlib.
https://github.com/aio-libs/async-timeout

[postlund]

Thank you @cdce8p! Can you fix the conflict? May I suggest that you move the conditional import code to pyatv/support/__init__.py and just do from pyatv.support import async_timeout instead? Maybe also add a comment/todo there that we can remove that part once the lowest supported python version is 3.11?

[cdce8p]

This should be good now. Modified the imports to add # noqa: F401 since they aren't used in pyatv.support themselves.