This deprecates the `xpack.watcher.history.cleaner_service.enabled` setting,
since all newly created `.watch-history` indices in 7.0 will use ILM to manage
their retention.
In 8.0 the setting itself and cleanup actions will be removed.
Resolves#32041
* Adding new MonitoredSystem for APM server
* Teaching Monitoring template utils about APM server monitoring indices
* Documenting new monitoring index for APM server
* Adding monitoring index template for APM server
* Copy pasta typo
* Removing metrics.libbeat.config section from mapping
* Adding built-in user and role for APM server user
* Actually define the role :)
* Adding missing import
* Removing index template and system ID for apm server
* Shortening line lengths
* Updating expected number of built-in users in integration test
* Removing "system" from role and user names
* Rearranging users to make tests pass
Lisa Cawley
Lee Hinman
Shaunak Kashyap