Bump version to 7.11.0

• Diff: https://gitlab.com/gitlab-org/gitlab-qa/compare/v7.10.0...22f72f2d9cfbf64c18f26c7fc74be7b6af6f5958

• Release notes:

### Other changes (CI, backstage)

- !771 Handle 429 Too Many Requests gracefully.

• Checklist before merging:

  • Diff link is up-to-date.
  • Based on the diff, lib/gitlab/qa/version.rb is updated, according to SemVer.
  • Release notes are accurate.

• Checklist after merging:

  • Update the release notes for the newly created tag.