Fix Prometheus integration with group/instance clusters

What does this MR do?

Apply post state transition (installation, deletion) callbacks of Prometheus cluster managed application onto projects which are connected on instance or group level.

Since number of affected project can be significant especially for instance level integration, I moved callbacks into background job, to avoid this process time outing user request.

Database migration which handles patching already existing data will be delivered in other MR.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Code review guidelines
• Merge request performance guidelines
• Style guides

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Reports #14857 (closed)