Use importlib_metadata with compat to Python 3.10/3.12 stdlib

[Taragolis]

That what I've accidentally found, that we install importlib_metadata only for Python 3.8 however in some places we might use in more modern versions of the Python when we use

try:
    import importlib_metadata as metadata
except ImportError:
   from importlib import metadata  

Right now importlib_metadata as well as (importlib_resources) presented into the Docker Image (2.8.4rc1), more like it comes from one of the dependency.
So this could be a situation that we unintendedly use some features from the backported packages and it works as expected, because this package also provide new feature which will added into the stdlib in the future, see compat table

importlib_metadata	stdlib
7.0	3.13
6.5	3.12
4.13	3.11
4.6	3.10
1.4	3.8

I've tried to found places where the behavior in stdlib changed (https://docs.python.org/3/library/importlib.metadata.html), and only found two places which we use in Airflow code base

• Entrypoints: in 3.6 (not relevant), 3.10 and 3.12
• Distribution metadata: In 3.10 (maybe also not our case)

This PR is attempt to prevent that something work just because some dependency install importlib_metadata and our code just always use importlib_metadata if it installed. This might help to detect some minor/major incompatabilities

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[Taragolis]

Not related to this one, but we also use importlib_resources but only in one place for the importlib.resources.files feature which added in Python 3.9 and changed in 3.12 (doesn't affect us)

airflow/airflow/providers_manager.py

Lines 49 to 52 in 83e83e2

	if sys.version_info >= (3, 9):
	from importlib.resources import files as resource_files
	else:
	from importlib_resources import files as resource_files

[Taragolis]

Ok.. seems like only one test should be fixed

[Taragolis]

Ok.. seems like only one test should be fixed

Need to fix mocked method

[potiuk]

Reviewed all the cases and confirmed it looks good according to the stdlib changes.

@uranusjr @ashb as you were involved in those, I think your pairs of eyes will be useful here as well.

[potiuk]

Rebase and merge @Taragolis ?

[Taragolis]

Rebase and merge @Taragolis ?

Yep, I will do it in the morning, I'm out of laptop