upgrade to pytest 8

[selfisekai]

No description provided.

[ppolewicz]

@selfisekai yapf would like to mess up your pretty formatting for the sake of consistency. Could you please add a # yapf: disable at the end of the affected lines to make sure your formatting is not vandalized by a bot?

Also, it appears that you've changed quotes in a bunch of lines. Do we really need to do it in this PR?

[selfisekai]

i've run ruff over it, that's how it happened

[ppolewicz]

Please run it again on test/unit/account_info/fixtures.py with --fix

[mjurbanski-reef]

the pytest-lazy-fixtures library is new and unknown, so I went and checked github repo and current tar/wheel releases. They seem clean - i.e. nothing shady going in there, but before updating the lockfile similar review should be done to make sure it's not a security hazard to dev machines.