Handle case when BroadcastMessage.current is nil

Closes #35094

See merge request !12860

Somehow Rails.cache.fetch occasionally returns `nil` values, which causes
this endpoint to crash.

Closes #35094

Make sure MergeRequest commit methods work when either compare_commits or merge_request_diff is set

Closes #35077

See merge request !12856

Increase width of dropdown menus

Closes #34989

See merge request !12809

Supplement Portuguese Brazil translation of Project Page & Repository Page

Closes #33672

See merge request !12156

Reload page after changing navigation preference

Closes #34968

See merge request !12833

Add more notes about developer seeds

See merge request !12836

Backport MR create service changes from EE

See merge request !12808

Prevent GitLab issue tracker spec from failing later specs

Closes #35042

See merge request !12835

Enable all feature flags by default in specs

See merge request !12832

Otherwise some features would go untested in non-specific contexts

I did need to disable the
`gitlab_git_diff_size_limit_increase`-feature in some specs since we
depend on diffs being expandable while the file we are testing on is
smaller than the increased limit.

Fix links to documentation describing the Prometheus service and its specifics.

Closes #34598

See merge request !12714

Truncate job on environment view

Closes #34835

See merge request !12818

Add Gitaly notes to Gitlab::Git, delete diff options

See merge request !12814

Closes #34968

Fix i18n string in commit page options dropdown

Closes #35036

See merge request !12831

Fix wording of nav toggle

See merge request !12796

Merge branch '34780-restricted-visibility-levels-in-admin-application-settings-looks-off' into 'master'

Fix wrong helper used for adding context for translations.

Closes #34780

See merge request !12731

Enable DeclarationOrder in scss-lint

See merge request !12805

Enable BangFormat in scss-lint

See merge request !12815

Additionally some missing translations were added

Update gitlab-shell to v5.3.1

Closes gitlab-shell#92

See merge request !12817

Migrate Workhorse SendBlob to Gitaly

Closes gitaly#356

See merge request !12313

MR branch link now links to tree instead of commits

Closes #34243

See merge request !12763

Backport "Automatically link Kerberos users and LDAP people" changes to CE

See merge request !12807

Add Italian translations of Pipeline Charts

Closes #34797

See merge request !12700

This fixes an issue where the merge request URLs for a push returned an error,
which made gitlab-shell show a stacktrace to the user.

Enable UnnecessaryParentReference in scss-lint

See merge request !12738