Policy resource for kind: Ingress

[brianehlert]

The ingress controller project uses the Policy object to define settings such as authentication and authorization.
50% of the user base insists on using the Ingress resource.

I propose adding a special annotation that allows associating a Policy resource with an Ingress resource. And thus being able to implement capabilities such as OIDC, auth_request, JWT, etc. using the Ingress resource.

One of the reasons is that this could potentially shorted design cost associated with bringing a number of VS exclusive capabilities to Ingress.

[brianehlert]

Also for #2822

[brianehlert]

Potentially for #4911
Actually, any time that the flexibility of Policy and multiple Policy attachment is desired with the Ingress resource.