Add ownerReferences in the metadata for NGINX data plane deployments

[salonichf5]

Is your enhancement request related to a problem? Please describe.
Add a .metadata.ownerReference to all Data Plane resources associated with a Gateway instance. So other tools can map out resource relationships

Community suggestion

What would you like to be added:
Add information about owner references for dataplane deployment.

Why this is needed:
To integrate better with third party tools.

[sjberman]

One thing I learned about ownerReferences, is that when the owner is deleted, all associated resources that reference that owner are also automatically cleaned up by k8s. So in theory, we could remove all the deletion logic from our control plane and when a user manually deletes their Gateway, k8s would delete all of those nginx resources for us. Could be worth exploring.