Remove :rbac_clusters feature flag

Closes #51009

See merge request gitlab-org/gitlab-ce!22096

Add pipeline.default_branch? mehod

See merge request gitlab-org/gitlab-ce!22102

Resolve "Add status message from within user menu"

Closes #51393 and #49075

See merge request gitlab-org/gitlab-ce!21643

Docs lock/unlock quick action

See merge request gitlab-org/gitlab-ce!22088

Port of create labels_as_hash_ concern, modify params for method

See merge request gitlab-org/gitlab-ce!21992

docs: moving repositories cleanup

See merge request gitlab-org/gitlab-ce!22099

[ci skip]

Update environment item empty state

See merge request gitlab-org/gitlab-ce!21976

Resolve "Add new "Overview" tab on user profile page"

Closes #49801

See merge request gitlab-org/gitlab-ce!21663

Fix MR discussion not loaded issue

Closes #51958

See merge request gitlab-org/gitlab-ce!21982

Includes commit stats in POST project commits API

Closes #51803

See merge request gitlab-org/gitlab-ce!21968

Helps to know if the pipeline ref matches  the project's default branch

Now that Auto DevOps can run in a RBAC enabled cluster from
https://gitlab.com/gitlab-org/gitlab-ce/issues/51942, we can now remove
the FF.

As the flag only governed if UI elements would appear or not when
creating/adding existing clusters; the effect of removing the FF would
be that the checkbox to choose to enable RBAC clusters will now always
appear.

Remove FF stubs from specs

Improve spec context names

* use `git` user
* formatting cleanup

Fix showing diff file header for renamed files

Closes #48887

See merge request gitlab-org/gitlab-ce!22089

Upgrade to Babel 7

Closes #43511

See merge request gitlab-org/gitlab-ce!22059

Update Development related gems

See merge request gitlab-org/gitlab-ce!22066

Add gl-button from gitlab-ui

See merge request gitlab-org/gitlab-ce!21941

Merge branch 'ce-7424-create-a-generic-event-listener-for-tracking-clicks-on-gitlab-com' into 'master'

CE port Resolve "Create a generic event listener for tracking clicks on GitLab.com"

See merge request gitlab-org/gitlab-ce!22002

Update CODEOWNERS for FE and .scss

See merge request gitlab-org/gitlab-ce!21913

Upgrade to latest version the following gems:
* Spring
* Bootsnap
* Thin
* webpack-rails
* pry-rails

Add element classes used in ee branch qa-257-group-saml-sso

See merge request https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/22074

QA: Revisit the login page when attempt to retry login

See merge request gitlab-org/gitlab-ce!22061

Uses Vue app to render part of job show page

See merge request gitlab-org/gitlab-ce!22028

Backport of "Use Geo log to remove files when migrated to object storage"

See merge request gitlab-org/gitlab-ce!22049

Fix placeholder note rendering.

Closes #48933

See merge request gitlab-org/gitlab-ce!22078

Moves stages dropdown into the new vue app

See merge request gitlab-org/gitlab-ce!21971