Goal: 

Based on the agreed CRD design, implement a top level notification bus definition for the whole OSCP deployment, then each listed in the components service operator inherits that, if the user does not override in the service specific template (SpecCore) in the OpenStackControlPlane CR.

Acceptance Criteria:

• PR has been merged, unit tests created and passing
• Default values for consumers of notifications retain the status quo to provide no upgrade impact for involved services
• Producing notifications is disabled by default (only for the services that produce it, excluding Nova) by changing  driver=messagingv2 -> driver=noop in configs. That is also to provide no upgrade impact for involved services