[OpAMP] implementation for central config

[jackshirazi]

• setup working group for resolving cross tea dependencies
  • Java side
  • OpAMP extension in Collector
  • Kibana side
• move OpAMP client code to EDOT Java
• connect OpAMP client with the dynamic config
• config options to start with:
  • instrumentation
  • sending

[jackshirazi]

The remaining functional item is the change of the opamp doc key to "elastic", which has now been committed to the collector extension. As that's a minor change, I consider this closed