CE Backport: Add styles for persistent notice banner

See merge request gitlab-org/gitlab-ce!19968

Updates to `.po` & `.pot` linting

Closes #46096 et #39292

See merge request gitlab-org/gitlab-ce!18779

port 5956-auto-devops-multi-cluster-help-text to CE

See merge request gitlab-org/gitlab-ce!19680

Allow trailing whitespace on blockquote fence lines

See merge request gitlab-org/gitlab-ce!19960

Redirect favicon.(png|ico) to actual favicon asset or upload

Closes #47840

See merge request gitlab-org/gitlab-ce!19956

Update README.md to clarify EFS is slow and not to use this guide.

See merge request gitlab-org/gitlab-ce!19852

Rails5 fix db check: connection execute returns integer instead of string

See merge request gitlab-org/gitlab-ce!19901

Merge branch 'blackst0ne-rails5-invalid-single-table-inheritance-type-group-is-not-a-subclass-of-namespace' into 'master'

Resolve "[Rails5] Invalid single-table inheritance type: Group is not a subclass of Namespace"

Closes #48014

See merge request gitlab-org/gitlab-ce!19918

Rails5 fix passing Group objects array into for_projects_and_groups milestone scope

Closes #48012

See merge request gitlab-org/gitlab-ce!19920

Document Custom build directories

Closes gitlab-runner#2211

See merge request gitlab-org/gitlab-ce!19664

fixed broken link to git cheat sheet

See merge request gitlab-org/gitlab-ce!19879

Resolve "Creating a deploy token doesn't bring back to the creation page"

Closes #46429

See merge request gitlab-org/gitlab-ce!19639

Render calendar feed inline when accessed from GitLab

Closes #47672

See merge request gitlab-org/gitlab-ce!19698

Merge branch 'blackst0ne-rails5-expected-the-response-to-have-status-code-ok-but-it-was-404' into 'master'

Resolve "[Rails5] expected the response to have status code :ok but it was 404"

Closes #48008

See merge request gitlab-org/gitlab-ce!19937

Rails5 update Gemfile.rails5.lock

Closes #48009

See merge request gitlab-org/gitlab-ce!19921

Resolve "[Rails5] expected: "/search?search=seed_project" got: nil"

Closes #48013

See merge request gitlab-org/gitlab-ce!19936

[Rails5] Fix pipeline_schedules_controller_spec

Closes #48011

See merge request gitlab-org/gitlab-ce!19919

Expose a clean_backtrace method from Gitlab::Profiler

See merge request gitlab-org/gitlab-ce!19894

Rails5 fix update_attribute usage not causing a save

Closes #47960

See merge request gitlab-org/gitlab-ce!19881

[Rails5] Explicitly set request.format for blob_controller

Closes #47921

See merge request gitlab-org/gitlab-ce!19876

With text/calendar as Content-Type, the browser always downloads the
content as a file (even ignoring the Content-Disposition header). We
want to display the content inline when accessed from GitLab, similarly
to the RSS feed.

Resolve "Milestone not updating in MR sidebar after selection"

Closes #47933

See merge request gitlab-org/gitlab-ce!19870

Make Gitaly wiki RPC's mandatory

See merge request gitlab-org/gitlab-ce!19701

Fix queue_name in Rails 5

Closes #47372

See merge request gitlab-org/gitlab-ce!19874

Remove the ci_job_request_with_tags_matcher

See merge request gitlab-org/gitlab-ce!19947

Optimise paused runners

See merge request gitlab-org/gitlab-ce!19946

We have long polling mechanism which is not being used by paused runners.
This makes the paused runner to generate a request every 3s,
where it could be fired only every 1h.

Harmonize theme preferences previews

See merge request gitlab-org/gitlab-ce!19916

Update all references to version to include `v` for consistency.

Closes gitlab-org/gitlab-runner#2211

Since Rails 5 request.format gets set by extension if it's not explicitly
set.
That means artifacts_controller#file no longer works as expected.
This commit explicitly sets request.format for artifacts_controller#file.

Refactor sessions_controller_spec to work both in rails4 and rails5.
Remove the stubbed `request.referer` method, set real header instead.