In issuable_base_service.rb the code processing labels is making
the update() method not as clear as it could be. Let's refactor
this code into a new assign_requested_labels() method.

While at it, lets rename labels_changing? into ids_changing?
as the method is not specific to labels and could be used with
other arrays of ids.

Instead of having to use a local variable in many places in
push_options_handler_service_spec.rb for the same error, let's
refactor this error using a common constant called
'error_mr_required'.

Add last_activity_on to BillableMember entity

See merge request gitlab-org/gitlab!52666

Remove ReadmeBlob since it isn't used

See merge request gitlab-org/gitlab!51270

Remove duplicated prepend of `EE::Types::DeprecatedMutations`

See merge request gitlab-org/gitlab!52066

Fix Debian packages API to raise 401 Unauthorized instead of a 404 Not Found

See merge request gitlab-org/gitlab!51734

Remove specific date in audit events spec

See merge request gitlab-org/gitlab!52995

Delete old redirect files in various docs directories

See merge request gitlab-org/gitlab!52997

These redirect files have expired and we
no longer need to maintain them. Server-side
redirects will remain in the gitlab-docs project

By default, the audit event search results are limited to the current
month. Having records created beyond that time range requires setting
the date filter or else they will not show up in the page.

The specific broken specs do not test date filter or order logic. Hence,
we could remove these dates.

Delete old redirect files in doc/user

See merge request gitlab-org/gitlab!52991

These redirect files have expired and we
no longer need to maintain them. Server-side
redirects will remain in the gitlab-docs project

Delete mock_deployment_service.rb

See merge request gitlab-org/gitlab!52966

Fix curl commands in vulnerability exports API

See merge request gitlab-org/gitlab!52918

Delete old redirect files in admin/analytics/api docs

See merge request gitlab-org/gitlab!52988

These redirect files have expired and we
no longer need to maintain them. Server-side
redirects will remain in the gitlab-docs project

Explain new sast / dependency_scanning error that was introduced in 13.4

See merge request gitlab-org/gitlab!47289

Fix auditor badging

See merge request gitlab-org/gitlab!52943

Apply new GitLab UI for badge and button in project's protected branch settings

See merge request gitlab-org/gitlab!52207

Remove container_class in project activity which removes extra padding

See merge request gitlab-org/gitlab!51878

Refactoring: Move search settings mount function to the search_settings directory

See merge request gitlab-org/gitlab!52834

Add iterations to bulk edit on project and group

See merge request gitlab-org/gitlab!51657

Remove obsolete DOMContentLoadedEventListener

See merge request gitlab-org/gitlab!52794

https://gitlab.com/gitlab-org/gitlab/-/merge_requests/51657

Apply new GitLab UI for inputs in admin/application_settings directory

See merge request gitlab-org/gitlab!52402

https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52402

Resolve "Fix tests that fail due to humanization of "29 days" vs "1 month""

See merge request gitlab-org/gitlab!52972

Remove ci_live_trace_use_fog_attributes feature flag

See merge request gitlab-org/gitlab!52939

Remove obsolete DOMContentLoadedEventListener

See merge request gitlab-org/gitlab!52778

Change Core to Free in misc docs

See merge request gitlab-org/gitlab!52945

Feat(EpicSelect): Migrate epic select

See merge request gitlab-org/gitlab!52528

Migrate our Epic seelct to
use our internal gitlab UI
compoenents