[Filebeat] Entity Analytics Input GA

[jamiehynds]

We now have several Entity Analytics integrations using the EA input under the hood.

We need to ensure the input is GA'd & fully supported and not left in Tech Preview for a long period of time.

This issue will track any blockers (if any) to GA'ing the input and ensure we GA asap.

[elasticmachine]

Pinging @elastic/security-service-integrations (Team:Security-Service Integrations)