Bump version to 7.24.0

• Diff: https://gitlab.com/gitlab-org/gitlab-qa/compare/v7.23.1...7cddc8b9e9bbaefa8f953348ccb0c650275aaf08
• Release notes:

### Fixes

- !867 Fix Rules on ee:repository_storage and ee:image jobs

### Other changes (CI, backstage)

- !869 Replace "feature::maintenance" with "type::maintenance"
- !868 Pass through all QA_ variables without explicitly defining them

• 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.