`kube-apiserver`: added `--authorization-config` flag for reading a configuration file containing an `apiserver.config.k8s.io/v1alpha1 AuthorizationConfiguration` object. The `--authorization-config` flag is mutually exclusive with `--authorization-modes` and `--authorization-webhook-*` flags. The `alpha` `StructuredAuthorizationConfiguration` feature flag must be enabled for `--authorization-config` to be specified. ([#120154](https://github.com/kubernetes/kubernetes/pull/120154), [@palnabarun](h...