Duplicated content related with configuring APM server and settings

The following files feel very similar and with duplicate information. It should be addressed and fixed at some point:
- reference/apm/cloud/apm-settings.md
- solutions/observability/apm/configure-apm-server.md

IMO the reference content `apm-settings` shouldn't probably have the narrative explanations about how to configure the APM server, and provide only the reference of the settings.

On the other hand the `configure-apm-server.md` feels much more complete and with more settings, but a lot of them appear to be duplicated.

There are two options here:
- Leave all the info in the solution doc
- Move all settings to the reference content and avoid duplicating the list of settings