* upstream/master: (507 commits)
  Add dropdowns documentation
  Convert migration to populate latest merge request ID into a background migration
  Set 0.69.0 instead of latest for codeclimate image
  De-duplicate background migration matchers defined in spec/support/migrations_helpers.rb
  Update database_debugging.md
  Update database_debugging.md
  Move installation of apps higher
  Change to Google Kubernetes Cluster and add internal links
  Add Ingress description from official docs
  Add info on creating your own k8s cluster from the cluster page
  Add info about the installed apps in the Cluster docs
  Resolve "lock/confidential issuable sidebar custom svg icons iteration"
  Update HA README.md to clarify GitLab support does not troubleshoot DRBD.
  Update license_finder to 3.1.1
  Make sure NotesActions#noteable returns a Noteable in the update action
  Cache the number of user SSH keys
  Adjust openid_connect_spec to use `raise_error`
  Resolve "Clicking on GPG verification badge jumps to top of the page"
  Add changelog for container repository path update
  Update container repository path reference
  ...

Convert migration to populate latest merge request ID into a background migration

See merge request gitlab-org/gitlab-ce!15440

Add dropdowns documentation

See merge request gitlab-org/gitlab-ce!15396

This is to smear updates over a few hours to avoid causing excessive
replication lag as seen in https://gitlab.com/gitlab-com/infrastructure/issues/3235.

Update database_debugging.md

See merge request gitlab-org/gitlab-ce!15434

Replace ci_status_path with pipeline_path

See merge request gitlab-org/gitlab-ce!15369

De-duplicate background migration matchers defined in spec/support/migrations_helpers.rb

See merge request gitlab-org/gitlab-ce!15441

Update HA README.md to clarify GitLab support does not troubleshoot DRBD.

See merge request gitlab-org/gitlab-ce!15428

Set 0.69.0 instead of latest for codeclimate image

See merge request gitlab-org/gitlab-ce!15445

Refactor  Cluster docs

Closes #39952

See merge request gitlab-org/gitlab-ce!15418

Resolve "lock/confidential issuable sidebar custom svg icons iteration"

Closes #37508

See merge request gitlab-org/gitlab-ce!15372

Isolate the fork network background migrations

See merge request gitlab-org/gitlab-ce!15393

Cache the number of user SSH keys

See merge request gitlab-org/gitlab-ce!15401

When a custom header logo is present, don't show GitLab type logo

See merge request gitlab-org/gitlab-ce!15410

Make sure NotesActions#noteable returns a Noteable in the update action

Closes #40208

See merge request gitlab-org/gitlab-ce!15421

Update license_finder to 3.1.1

Closes #34955 et #40020

See merge request gitlab-org/gitlab-ce!15319

By caching the number of personal SSH keys we reduce the number of
queries necessary on pages such as ProjectsController#show (which can
end up querying this data multiple times).

The cache is refreshed/flushed whenever an SSH key is added, removed, or
when a user is removed.

Adjust openid_connect_spec to use `raise_error`

Closes #40093

See merge request gitlab-org/gitlab-ce!15420

Backport delete epic changes

Closes #40162

See merge request gitlab-org/gitlab-ce!15414

Change logic of repo name and slugs in docs review script

See merge request gitlab-org/gitlab-ce!15395

Use relative git object paths to construct absolute ones before setting Env

See merge request gitlab-org/gitlab-ce!15376

Using the `raise_error`-matcher instead of `throw_symbol` makes sure
our after blocks get called in the test suite.

Add basic docs for troubleshooting database problems

See merge request gitlab-org/gitlab-ce!15416

Add readme only default project view preference

See merge request gitlab-org/gitlab-ce!15415

Add an attributes bag class as a GitalyClient helper

See merge request gitlab-org/gitlab-ce!15346