This PR does the following things:

1. add new registry api under resources.kubesphere.io/v1alpha3
2. deprecate registry api v1alpha2

Registry API v1alpha2 uses docker client to authenticate image registry
secret, which depends on docker.sock. We used to mount host
`/var/run/docker.sock` to deployment. It will prevent us imgrating to
containerd since no `docker.sock` exists. Registry API v1alpha3 comes to
rescure, it wraps library go-containerregistry and compatible with
docker registry, Harbor etc.

vendor/github.com/google/go-containerregistry/pkg/authn/anon.go

@@ -0,0 +1,26 @@
+// Copyright 2018 Google LLC All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package authn
+
+// anonymous implements Authenticator for anonymous authentication.
+type anonymous struct{}
+
+// Authorization implements Authenticator.
+func (a *anonymous) Authorization() (*AuthConfig, error) {
+	return &AuthConfig{}, nil
+}
+
+// Anonymous is a singleton Authenticator for providing anonymous auth.
+var Anonymous Authenticator = &anonymous{}