This MR adds a new, tiny `import/namespaces` controller.

This controller lists available namespaces for import. Moving this to
separate controller has following rationale:

* `namespaces` are required for each controller, provided in `import/`
  folder. They are identical, does not have any customization, etc.

* ATM `namespaces` are returned as the part of `status` in
  `base_controller`. With our intention to add pagination to `status` we
  need to move "static part of the content" (namespaces) away from part,
  which will be paginated (repos)

Related issues:

* https://gitlab.com/gitlab-org/gitlab/-/issues/233059
* https://gitlab.com/gitlab-org/gitlab/-/issues/222889
* https://gitlab.com/gitlab-org/gitlab/-/issues/27370

Remove build_report_summary feature flag

See merge request gitlab-org/gitlab!37629

Add GraphQL mutation to set the epic of an issue

See merge request gitlab-org/gitlab!38494

Show iteration report in projects

See merge request gitlab-org/gitlab!37979

Fix monitoring panel preview for small viewports

See merge request gitlab-org/gitlab!38737

Remove unused ml_IN locale file

See merge request gitlab-org/gitlab!38912

Merge branch '228532-remove-feature-flag-that-controls-the-license-approval-widget-on-the-license-compliance-page' into 'master'

Remove license_approvals feature flag

See merge request gitlab-org/gitlab!38877

Run pages configuration update in a worker

See merge request gitlab-org/gitlab!38524

Geo - Remove support for Foreign Data Wrapper

See merge request gitlab-org/gitlab!38718

Replace deploy freeze mock_data usage with frontend fixture

See merge request gitlab-org/gitlab!38532

Clarify inline coverage not on dot com docs

See merge request gitlab-org/gitlab!38922

- Inline code coverage visualization is not available on dot com. The
  documentation didn't reflect that clearly so this commit makes it
clear that the feature is behind a feature flag, disabled by default.

Track wiki page views in usage data

See merge request gitlab-org/gitlab!38784

Simplify Advanced Search code_analyzer regex complexity

See merge request gitlab-org/gitlab!37372

Add group_id column to the services table

See merge request gitlab-org/gitlab!38499

Merge branch '222436-ux-pajamas-implementation-move-buttons-in-settings-operations-to-the-right' into 'master'

Move Buttons in Settings > Operations to the right

Closes #222436

See merge request gitlab-org/gitlab!38652

Follow pajamas guidelines, move buttons to right
Git rebasing with master

Introduce HashedPath class

See merge request gitlab-org/gitlab!38826

This class centralizes the business logic of
disk path for a given uploader.

Explain what Ci::PipelineArtifact is

See merge request gitlab-org/gitlab!38926

Add specs for destroy_conditionally and check_unmodified_since!

Closes #229181

See merge request gitlab-org/gitlab!37520

Refactor test show endpoint

See merge request gitlab-org/gitlab!38809

Optimise ExtractsRef when repository does not have ambiguous refs

See merge request gitlab-org/gitlab!38484

Merge branch '219758-replace-gl-deprecated-button-with-gl-button-in-app-assets-javascripts-custom_metrics' into 'master'

Resolve "Migrate custom metric form buttons"

Closes #219758

See merge request gitlab-org/gitlab!38896

Since Gitlab 13.2, Geo don't rely on FDW

DAST On-Demand Scans - Use existing site profiles for scans - Frontend

See merge request gitlab-org/gitlab!37604

Improve prometheus queries used in Pod health dashboard

See merge request gitlab-org/gitlab!38802

- Aggregate by container where possible.
- Correct the disk I/O queries.

Add AmazonEKSClusterPolicy to Kubernetes instructions

See merge request gitlab-org/gitlab!38853

Update Geo docs to reflect checkbox removal

See merge request gitlab-org/gitlab!38798

Perform redis UNLINK instead of DEL in ElasticsearchEnabledCache

See merge request gitlab-org/gitlab!38410

Add Pages domain configuration docs

See merge request gitlab-org/gitlab!37662

Replaced deprecated button

Closes #219867

See merge request gitlab-org/gitlab!38679