Update dependency pytest to v8

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
pytest (source, changelog)	>=6,<8 -> >=8,<9

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Release Notes

pytest-dev/pytest (pytest)

### [`v8.0.0`](https://togithub.com/pytest-dev/pytest/compare/7.4.4...8.0.0) [Compare Source](https://togithub.com/pytest-dev/pytest/compare/7.4.4...8.0.0)

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