Start CpuMonitorService as part of the core services startup on

debuggable builds.

- CpuMonitorService is currently used to report the CPU stats for
  debugging in bugreport. So, enable this service only on debuggable
  builds.
- Once the Android JobScheduler starts using this service,
  the CpuMonitorService will be started on all builds and not just on
  debuggable builds.

Test: m
Bug: 242722241

Change-Id: I8b701c8c1e8bfc35023ca8f4bd6247aa8bf385ab