Enable long-running processes in ControllerExecutionBB

Enable long-running processes in ControllerExecutionBB

Instead of blocking a thread while waiting for controller response,
ControllerExecutionBB is now using camunda receive task to support
long running processes without increasing the camunda job timeout.

A new property was added to configure the gRPC client's keep alive
ping mechanism, which will identify connection issues and prevent
the process getting stuck when the controller crashes.

Issue-ID: SO-3953
Signed-off-by: Jozsef Csongvai <jozsef.csongvai@bell.ca>
Change-Id: Iaf6438dba76e715dba846bf45ef47b6a91239c4a