merge master to 1.10, with fixes (#7682)

cn/docs/user-guide/nginx-secure-app.yaml

@@ -17,11 +17,14 @@ spec:
   selector:
     run: my-nginx
 ---
-apiVersion: apps/v1beta1
+apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: my-nginx
 spec:
+  selector:
+    matchLabels:
+      run: my-nginx
   replicas: 1
   template:
     metadata:

cn/docs/user-guide/run-my-nginx.yaml

@@ -1,8 +1,11 @@
-apiVersion: apps/v1beta1
+apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: my-nginx
 spec:
+  selector:
+    matchLabels:
+      run: my-nginx
   replicas: 2
   template:
     metadata: