Include configuration for the new `ValidatingAdmissionPolicy` and
`ValidationAdmissionPolicyBinding` APIs so that Kustomize can natively configure
the `policyName` field in `ValidatingAdmissionPolicyBinding` with the transformed
name of `ValidatingAdmissionPolicy`.
This PR is an effort towards internalizing public APIs.
It moves some of the builtinconstants to internal/
Signed-off-by: Varsha Prasad Narsing <varshaprasad96@gmail.com>