ruff check and ruff format github action

[maurycy]

This is very similar to what was done in pyperformance:

• https://github.com/python/pyperformance/blob/main/.pre-commit-config.yaml
• https://github.com/python/pyperformance/blob/main/.github/workflows/lint.yml

ruff is used since fdfd482, but was never enforced.

I can split ruff check and ruff format into two separate PRs for readability, similarly to python/pyperformance#405 and python/pyperformance#410 but ruff check is clean here:

2026-01-02T21:25:39.780432000+0100 maurycy@gimel /Users/maurycy/src/pyperf (maurycy-ruff-ci) % uvx ruff check
All checks passed!

The PR also adds pre-commit, Dependabot and updates Github Action checkout.

[vstinner]

I'm not convinced that ruff format makes the code easier to read/maintain.

@corona10: Do you have an opinion on this change?

[maurycy]

@vstinner Thank you for taking a look.

It's customizable. We can figure out a set of extend-select, extend-ignore etc. flags that minimize the amount of changes, yet enforce some rules.

Some background here: I was thinking about plugging in profiling.sampling over the holidays (the idea was to run all the pyperformance benchmarks with it). The attempt made me realize that's not exactly trivial to do it well but also there's no style to adher to.

I can remove the format part, and leave the rest (ie: pre-commit, Gihub action updates and Dependabot.)

[vstinner]

You should write a separated PR for these changes and the .github/dependabot.yml change.