* Support namespace access from cel expression in validatingadmissionpolicy.
* Whitelist the exposed fields in namespace object and add test
* better handling of cluster-scoped resources.
* [API REVIEW] namespaceObject in Expression doc.
* compatibility with composition.
* generated: ./hack/update-codegen.sh && ./hack/update-openapi-spec.sh
* workaround namespace of namespace is unexpectedly set.
* basic test coverage for namespaceObject.
---------
Co-authored-by: Jiahui Feng <jhf@google.com>
13172cba5c