- Migration updates existing groups to "owner", then sets default to
  "maintainer" so that new groups will default to that
- Update spec examples

Both with subgroup_creation_level set to owners and to maintainers.
Also fixed the naming of some other examples in the same spec as they
were contradicting what they were actually performing in the test.
These examples were probably copy/pasted, and not renamed.

For both groups_controller and admin/groups_controller

This setting is at the group level only. The default is specified to
be maintainers and owners.

**Specs only**, all failing.

All specs passing

- Change the two existing feature examples that create a subgroup to
  elucidate that the owner is creating the subgroup

- Nest two more specs inside the 'subgroup support' context detailing
  what happens when a maintainer attempts to add a subgroup (one with
  subgroup support, and one without)

Removes EE differences for app/views/layouts/fullscreen.html.haml

Closes gitlab-ee#12550

See merge request gitlab-org/gitlab-ce!30403

Adding order by to list runner jobs api.

Closes #51794

See merge request gitlab-org/gitlab-ce!29629

Backport of https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/14328

See merge request gitlab-org/gitlab-ce!30003

Remove unused Gitaly feature flags

See merge request gitlab-org/gitlab-ce!30302

CE Port: Extend `MergeToRefService` to create merge ref from an arbitrary ref

See merge request gitlab-org/gitlab-ce!30361

CE Port: Split AutoMergeService interfaces into two `cancel` and `abort`

See merge request gitlab-org/gitlab-ce!30249

Create private merge requests in forks

Closes #58583

See merge request gitlab-org/gitlab-ce!29984

Fix call to removed GitPushService

See merge request gitlab-org/gitlab-ce!30222

Removes EE differences for app/views/profiles/preferences/show.html.haml

Closes gitlab-ee#12553

See merge request gitlab-org/gitlab-ce!30397

Fix divergence graph loading error

Closes #64143

See merge request gitlab-org/gitlab-ce!30393

https://gitlab.com/gitlab-org/gitlab-ce/issues/58583

Update dependency @gitlab/ui to ^5.3.2

See merge request gitlab-org/gitlab-ce!30259

Support note position tracing on an image

See merge request gitlab-org/gitlab-ce!30158