Update merge request's merge_commit after branch update

Closes #48889

See merge request gitlab-org/gitlab-ce!22794

Improve error message when attempting to reopen MR and there's a new open MR for the same branch

Closes #22548

See merge request gitlab-org/gitlab-ce!22326

Backports some changes from gitlab-ee!7885

See merge request gitlab-org/gitlab-ce!23637

Fix transaction pollution in Shard.by_name

See merge request gitlab-org/gitlab-ce!23655

Documentation for "`only/except: merge-requests` for merge request pipelines"

Closes #54511 and #15310

See merge request gitlab-org/gitlab-ce!23397

Show primary button when all labels are prioritized

Closes #54467

See merge request gitlab-org/gitlab-ce!23648

[Documentation] Fix minor issues in search API doc

Closes #54959

See merge request gitlab-org/gitlab-ce!23645

If a commit has two parents, one is direct ancestor, and one is not,
and the order of `commits` is in such fashion that the non-ancestor
side is visited first, the commit would be determined as non-ancestor,
when in fact it can be.

Therefore we should first determine all direct ancestors
prior to analyzing.

Remove Sidekiq::Testing in RepositoryController spec

See merge request gitlab-org/gitlab-ce!23653

CE Backport: Fix labels tooltip in collapsed Epics sidebar

See merge request gitlab-org/gitlab-ce!23647

Fix duplicate boardsStore variable in milestone select

Closes #54139

See merge request gitlab-org/gitlab-ce!23625

Update docs' Dangerfile

See merge request gitlab-org/gitlab-ce!23620

Use FastDestroy for deleting uploads

Closes #46069

See merge request gitlab-org/gitlab-ce!20977

Add CI/CD build encrypted tokens (after revert)

Closes #52342

See merge request gitlab-org/gitlab-ce!23649

Analyze new commits graph to determine each commit's merge commit.

Fix "merged with [commit]" info for merge requests being merged
automatically by other actions.

Allow analyzing upto the relevant commit

Fixed misreported error codes and elaborated

See merge request gitlab-org/gitlab-ce!23642

Add a flag to use a subquery for group issues search

See merge request gitlab-org/gitlab-ce!23445

Document `/help` tests

See merge request gitlab-org/gitlab-ce!23469

Update gitlab runner helm chart to 0.1.39

Closes gitlab-runner#3807

See merge request gitlab-org/gitlab-ce!23633

Brings back 1e8f1de0 reverted in !23644

Closes #52342

See merge request gitlab-org/gitlab-ce!23436

Fix broken seeder 11.6

Closes #54949

See merge request gitlab-org/gitlab-ce!23608

Truncate merge request titles with periods instead of ellipsis

Closes #54862

See merge request gitlab-org/gitlab-ce!23558

Add section about enabling feature flag in development

See merge request gitlab-org/gitlab-ce!23634

Pass commit when posting diff discussions

See merge request gitlab-org/gitlab-ce!23371

Dropdown: Make Identicons of a subgroup in the breadcrumb dropdown not take a whole line

Closes #51138 and #54026

See merge request gitlab-org/gitlab-ce!23062