Update plugin registration documentation about entry points about flake8 HOT 4 CLOSED

Yes I was thinking more about linking the packaging user guide, and explicitly stating "we give an example with setuptools (and setup.py) but this is now a standard blabla.."

Will probably have time to work on this by the end of the week

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Sure. If merge a PR that updates that. For reference pkg_resources is also deprecated for a library in the standard library so it's worth mentioning that too

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It could be great add something about setting up by pyproject.toml file.

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The packaging user guide already has examples for all types of package metadata config so that doesn't need to be replicated here

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