This reverts commit 51340f9b47e8339cdabce11d0a17ac724278bff0.

Prevent EE backport migrations from running if CE is not migrated

Closes #63612

See merge request gitlab-org/gitlab-ce!30002

If a user upgraded to any GitLab 11.x EE version but switched
back to CE, it's possible the state of the EE tables are not
in the right state for the EE backport migration to work properly.
In particular, there were three tables that had trouble:

* epics
* geo_event_log
* vulnerability_feedback

The EE backport migration would fail while trying to add foreign key
constraints because a key didn't exist in the table. This happens
because any EE migration that add or removed columns between v11.0.0 and
v11.11.3 are not guaranteed to be applied in an CE installation. The EE
backport schema does not individually backport these migrations.

We now check if certain columns are present to determine whether
the backport migration is in the proper state. CE users are required
to upgrade to v11.11.3 EE if they ever installed EE previously before
they can go back to v12.x CE.

Tested via:

```
git checkout -f v11.0.0-ee
bundle exec rake db:reset
git checkout .; git checkout -f v11.11.3
bundle exec rake db:migrate
git checkout .; git checkout -f v12.0.0
bundle exec rake db:migrate
<failure happens>
```

Changes migration and all other places the attribute is used

Adds an instance setting to limit display of time tracking
values to hours only

Add index for pages domain ssl auto renewal
Add PagesDomain.needs_ssl_renewal scope
Add cron worker for ssl renewal
Add worker for ssl renewal
Add pages ssl renewal worker queues settings

Automatically update MR merge-ref along merge status

See merge request gitlab-org/gitlab-ce!29569

Adds enum certificate_source to pages_domains table
with default manually_uploaded

Mark certificates as 'gitlab_provided'
if the were obtained through Let's Encrypt

Mark certificates as 'user_provided' if they were uploaded through
controller or api

Only show private key in domain edit form if it is 'user_provided'

Only show LetsEncrypt option if is enabled by application settings
(and feature flag)

Refactor and fix some specs to match new logic

Don't show Let's Encrypt certificates as well

Disallow `NULL` values for `geo_nodes.primary` column

Closes gitlab-ee#12061

See merge request gitlab-org/gitlab-ce!29818

Migrate managed clusters that aren't using managed features to unmanaged

Closes #62772

See merge request gitlab-org/gitlab-ce!29251