up min pytest version from 4.6 to 7.0

[even-even]

Hello.
In this PR:

1. up minimum supported pytest version from 4.6 to 8.0.0
2. up unit tests run in pytest from 8.x.x to 9.0.2

[blake-r]

I think we should maintain compatibility with at least pytest 7.0.0, as it was the first version to fully support Python 3.10 (which is the oldest supported version) and is still used.

[even-even]

I think we should maintain compatibility with at least pytest 7.0.0, as it was the first version to fully support Python 3.10 (which is the oldest supported version) and is still used.

Edit minimum pytest version 8.0 -> 7.0 and edit in PR title_label