Delete Prometheus Alerts MonitoringManager

[agrare]

This was only supported on OCPv3 and is not expected to be reimplemented in the future.

Based on: #506

NOTE I split this out from #506 because we might want to backport that (it causes user confusion) where as this is strictly a backend cleanup that also will require some data migrations to delete any old records.

[kbrock]

kicking

[kbrock]

ok, looks like the test failure is trivial but legit. The list has changed:

       the missing elements were: [
         "manageiq-providers-openshift_monitoring_manager_event_catcher.target",
         "manageiq-providers-openshift_monitoring_manager_event_catcher@.service"
       ]
     # ./spec/manageiq/spec/models/miq_worker/systemd_common_spec.rb:19:in `block (3 levels) in <top (required)>'

Confused why this is showing up here though.
Maybe a rebase would fix?

[agrare]

The test is correct I forgot to remove the systemd unit files for the deleted worker classes

[miq-bot]

Checked commit agrare@8c101b1 with ruby 2.6.10, rubocop 1.28.2, haml-lint 0.35.0, and yamllint
0 files checked, 0 offenses detected
Everything looks fine. 🍪

[miq-bot]

This pull request has been automatically marked as stale because it has not been updated for at least 3 months.

If these changes are still valid, please remove the stale label, make any changes requested by reviewers (if any), and ensure that this issue is being looked at by the assigned/reviewer(s).

[miq-bot]

This pull request is not mergeable. Please rebase and repush.

[agrare]

Closing in favor of #518