Convert site to Hugo (#8316)

This commit converts content and layout to use Hugo.

content/cn/docs/tasks/inject-data-application/secret-envars-pod.yaml

@@ -0,0 +1,19 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: secret-envars-test-pod
+spec:
+  containers:
+  - name: envars-test-container
+    image: nginx
+    env:
+    - name: SECRET_USERNAME
+      valueFrom:
+        secretKeyRef:
+          name: test-secret
+          key: username
+    - name: SECRET_PASSWORD
+      valueFrom:
+        secretKeyRef:
+          name: test-secret
+          key: password