Added mirrors-pytest to all-repos.yaml

[Repiteo]

my new repository:

• is added to the bottom or with existing repos from the same account
• contains a license
• is not language: system, language: script, language: docker, or language: docker_image
• does not contain "pre-commit" in the name

[asottile]

pytest should not be run with pre-commit

[Repiteo]

Damn, couldn't have chosen a more qualified person to shoot this idea down lmao

[asottile]

there's a lot of writing about this amongst the pre-commit and pytest issue tracker(s) -- here's a short summary: pre-commit/pre-commit-hooks#291 (comment)

[Repiteo]

D'oh! I only checked the PRs for pytest, somehow didn't think to check issues as well. At least my specific use-case is rather small so I can get away with using it for the time being, but I can certainly see why you wouldn't want to "endorse" this practice by adding it officially.