Update pytest-cov to 6.0.0

[pyup-bot]

This PR updates pytest-cov from 5.0.0 to 6.0.0.

Changelog

6.0.0

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* Updated various documentation inaccuracies, especially on subprocess handling.
* Changed fail under checks to use the precision set in the coverage configuration.
Now it will perform the check just like ``coverage report`` would.
* Added a ``--cov-precision`` cli option that can override the value set in your coverage configuration.
* Dropped support for now EOL Python 3.8.

Links

• PyPI: https://pypi.org/project/pytest-cov
• Changelog: https://data.safetycli.com/changelogs/pytest-cov/
• Repo: https://github.com/pytest-dev/pytest-cov