Expand expedite label to revert MRs

Context

With gitlab-org/quality/triage-ops!1834 (merged), we have triage-ops tagging MRs with pipeline:expedite if the MR title starts with Revert or revert.

What does this MR do?

Step 2 of gitlab-org/ruby/gems/gitlab-dangerfiles#28 (comment 1209372811).

If your MR starts with Revert or revert, and have the pipeline:expedite label, it will skip some jobs 🎉

This MR ensures that the jobs will be skipped when those conditions are met.

Screenshots

Before applying pipeline:expedite label

https://gitlab.com/gitlab-org/gitlab/-/pipelines/723523701

After applying pipeline:expedite label

https://gitlab.com/gitlab-org/gitlab/-/pipelines/728028785

From Draft to Ready

• Finish Step 1 of gitlab-org/ruby/gems/gitlab-dangerfiles#28 (comment 1209372811)
• gitlab-org/quality/triage-ops!1834 (merged) is merged
• Test the following:
  • Change the MR title to start with revert or Revert
  • Apply the pipeline:expedite label
  • Trigger a new pipeline
  • Ensure that we skipped the coverage-frontend job in that new pipeline

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.