Also adds unit tests for Runtime::Feature.enabled?

EE: Show cluster link on job page

See merge request gitlab-org/gitlab-ee!16361

When the user has permissions (ie. maintainer) they can follow this link
to the cluster page. Otherwise they can always view this cluster name.
This is to implement
https://gitlab.com/gitlab-org/gitlab-ce/issues/55095 and helps users
debug cluster deployments.

This cluster detail will be used to show cluster link in the job output
as per https://gitlab.com/gitlab-org/gitlab-ce/issues/55095 . We needed
to create a new model here for ClusterBasicEntity as the only other
model ClusterStatus had much more data than necessary including nested
model lookups for applications.

Use a unique metric tag for each email handler

See merge request gitlab-org/gitlab-ee!16577

Otherwise there is a possibility that within the same
Sidekiq process, that same event with different
metrics_params will cause Prometheus to
throw an error, "labels must have the same signature"

Add end-to-end test for issue mention

See merge request gitlab-org/gitlab-ee!16485

Merge branch '65473-when-the-branch-name-is-a-divider-or-separator-the-project-home-page-cannot-display-the-branch-name-correctly-ee' into 'master'

EE Port of CE !32198

See merge request gitlab-org/gitlab-ee!16165

De-quarantine plan end-to-end test

Closes gitlab-org/quality/staging#68

See merge request gitlab-org/gitlab-ee!16526

Disable editing of the `License-Check` approval rule name.

See merge request gitlab-org/gitlab-ee!16149

* Allow editing during rule creation
* Add Changelog entry
* Updates the backend to prevent the `License-Check` rule name from
being edited.

Add e2e tests for project audit logs

See merge request gitlab-org/gitlab-ee!16012

Added E2E tests for SAST reports

Closes gitlab-org/quality/testcases#124 and gitlab-org/quality/testcases#131

See merge request gitlab-org/gitlab-ee!16415

Additionally updated fixture to provide SAST report

Notably, this changeset actually fixes ALL uses of gl_dropdown

Update explicit headers to new format

Cases tested:  
- Separator  
- Divider  
- Header

Basic Intent: Allow all branch names without accidentally creating
layout or backstage DOM. e.g. a branch named `separator` should never
create a separator `li` element.  

Ideally, there should never be a string that could cause this kind of 
conflict.  

Implementation: All of `GitLabDropdown.renderItem` is extracted to a 
standalone module.  

To render a divider or separator, consumers must now pass in an object 
like `{ "type": "divider" }` or `{ "type": "separator" }`   

Notable choices:  
- All of the functions have a cyclomatic complexity of 3 or less
    - See: https://en.wikipedia.org/wiki/Cyclomatic_complexity
    - Note the "Correlation to number of defects" section
    - While software complexity may not have a directly causal
      relationship with defects, less complex software is generally
      easier to reason about, and **may** reduce defects.
      I personally try to maintain complexity of no higher than 3.
- Everything other than the branch names fix matches past behavior 
exactly
    - Including:
        - Unused variables
        - Class list order

Enable mock setup to make onboarding development easier

See merge request gitlab-org/gitlab-ee!15492

- it used to be complicated to setup your local environment
  in order to work on the onboarding tour.  Full of
  temporary changes that would need backed out
- now we can work on it merely by enabling the Feature flag
  :user_onboarding

Add pod status for review-app release in debug

See merge request gitlab-org/gitlab-ee!16522

Remove EE specific checks

See merge request gitlab-org/gitlab-ee!16513

Remove orphaned project registries

Closes #13158

See merge request gitlab-org/gitlab-ee!15021

I have analyzed the execution of this test in the quarntine jobs
of some MRs, and in all of the executions that I looked it has
passed, so I'm de-quarantining it, but I'll keep an eye on it
in case it fails again.

[Backend] Step 3 API for trials

See merge request gitlab-org/gitlab-ee!16339

We need to create Leads when customers are requesting a trial for
GL.com. In order to do it we're going to use a service that will call a
custom endpoint on the subscription portal.

Ensure right order of processing multipart requests

See merge request gitlab-org/gitlab-ee!16461

[EE] Fix broken master by ensuring the EE version of ListIssue is imported if available

Closes #31797 and #31798

See merge request gitlab-org/gitlab-ee!16506

Add warning about LE wildcard certificate for pages

See merge request gitlab-org/gitlab-ce!32643

Apply suggestion to doc/user/project/pages/custom_domains_ssl_tls_certification/lets_encrypt_integration.md

Create self-monitoring project in background migration

See merge request gitlab-org/gitlab-ce!32819

- A regular migration caused problems such as
https://gitlab.com/charts/gitlab/issues/1565.

Fix encoding error in MR diffs

Closes #61841

See merge request gitlab-org/gitlab-ce!32862

Fix code docs for RuboCop's helper methods

See merge request gitlab-org/gitlab-ce!32937