Add a check-commit-guidelines job to commit-checker.yml
that runs scripts/check-commit on every new commit, so
the Co-authored-by ban holds in CI too. PR events check
out the base ref, keeping the executed script trusted.
AI-assisted-by: muse-spark-1.3-contributor
Signed-off-by: Andrey Antukh <niwi@niwi.nz>
3458b2f2e5