Update setuptools to 49.4.0

[pyup-bot]

This PR updates setuptools from 49.3.0 to 49.4.0.

Changelog

49.4.0

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* 2310: Updated vendored packaging version to 20.4.

49.3.2

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* 2300: Improve the ``safe_version`` function documentation
* 2297: Once again, in stubs prefer exec_module to the deprecated load_module.

49.3.1

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* 2316: Removed warning when ``distutils`` is imported before ``setuptools`` when ``distutils`` replacement is not enabled.

Links

• PyPI: https://pypi.org/project/setuptools
• Changelog: https://pyup.io/changelogs/setuptools/
• Repo: https://github.com/pypa/setuptools

[coveralls]

Coverage remained the same at 86.168% when pulling dc51a41 on pyup-update-setuptools-49.3.0-to-49.4.0 into 8a893ab on master.

[pyup-bot]

Closing this in favor of #246