Merge pull request #44197 from Random-Liu/dockershim-only-mode

Automatic merge from submit-queue

Add dockershim only mode

This PR added a `experimental-dockershim` hidden flag in kubelet to run dockershim only.

We introduce this flag mainly for cri validation test. In the future we should compile dockershim into another binary.

@yujuhong @feiskyer @xlgao-zju 
/cc @kubernetes/sig-node-pr-reviews

pkg/generated/openapi/zz_generated.openapi.go

@@ -13964,6 +13964,13 @@ func GetOpenAPIDefinitions(ref openapi.ReferenceCallback) map[string]openapi.Ope
 								Format:      "",
 							},
 						},
+						"experimentalDockershim": {
+							SchemaProps: spec.SchemaProps{
+								Description: "Enable dockershim only mode.",
+								Type:        []string{"boolean"},
+								Format:      "",
+							},
+						},
 						"experimentalFailSwapOn": {
 							SchemaProps: spec.SchemaProps{
 								Description: "Tells the Kubelet to fail to start if swap is enabled on the node.",