Use ResourceLabelEvent for tracking label changes

Closes #48483

See merge request gitlab-org/gitlab-ce!21281

Port cleanup tasks to use Gitaly

Closes #40529 and gitaly#954

See merge request gitlab-org/gitlab-ce!21588

Encode remote root ref

See merge request gitlab-org/gitlab-ce!21583

Rake tasks cleaning up the Git storage were still using direct disk
access, which won't work if these aren't attached. To mitigate a
migration issue was created.

To port gitlab:cleanup:dirs, and gitlab:cleanup:repos, a new RPC was
required, ListDirectories. This was implemented in Gitaly, through
https://gitlab.com/gitlab-org/gitaly/merge_requests/868.

To be able to use the new RPC the Gitaly server was bumped to v0.120.

This is an RPC that will not use feature gates, as this doesn't scale on
.com so there is no way to test it at scale. Futhermore, we _know_ it
doesn't scale, but this might be a useful task for smaller instances.

Lastly, the tests are slightly updated to also work when the disk isn't
attached. Eventhough this is not planned, it was very little effort and
thus I applied the boy scout rule.

Closes https://gitlab.com/gitlab-org/gitaly/issues/954
Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/40529

dedupe frontend dependencies

See merge request gitlab-org/gitlab-ce!21590

Update robots.txt (#51167)

See merge request gitlab-org/gitlab-ce!21585

Improved IDE commit flow

Closes #48182

See merge request gitlab-org/gitlab-ce!21471

Check if key is present with string not symbol

Closes #51225

See merge request gitlab-org/gitlab-ce!21589

moved heights into variables

Closes #48182

don't add trailing = when in urlParamsToArray function

See merge request gitlab-org/gitlab-ce!21179

closes gitlab-org/gitlab-ce#51225

Fix NamespaceUploader.base_dir for remote uploads

See merge request gitlab-org/gitlab-ce!21308

Added file templates to the Web IDE

Closes #47947

See merge request gitlab-org/gitlab-ce!21245

Import common metrics into database.

Closes gitlab-ee#6948

See merge request gitlab-org/gitlab-ce!21459

Clarify CodeSandbox works for private projects

See merge request gitlab-org/gitlab-ce!21579

improved variable & prop names

fixed content not updating in editor when changing template

Closes #47947

[QA] Change Test::Sanity::Failing to Test::Sanity::Framework

See merge request gitlab-org/gitlab-ce!21568

Resolve "Improve handling of projects shared with a group"

Closes #44005

See merge request gitlab-org/gitlab-ce!20262