Update version to 7.30.0

• Diff: https://gitlab.com/gitlab-org/gitlab-qa/-/compare/v7.29.1...7a76fd0cb6872e227b5045f90dd35c330d771361

• Release notes:

### New scenarios and scenario updates

- !960 Add a global server pre-receive hook with customised error message

### Fixes

- !956 Ignore screenshot section if upload failed
- !967 Let version sanity test check dev repos
- !968 Mock skip_pull in specs to prevent failures when ENV is set

### Other changes (CI, backstage)

- !971 Use info level log with colorized option
- !970 Skip reporting Net::ReadTimeout failures

• 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.