Consolidate YAML files [part-5] (#9258)

* Consolidate YAML files [part-5]

This PR relocates the yaml files used in stateless application
guestbook. This PR also fixes the list numbering and code block
problems in the page.

Note that neither code blocks nor note callouts live happily inside a
numbered list, so this PR moves them out of such lists.

* Update examples_test.go

content/en/examples/application/guestbook/frontend-service.yaml

@@ -0,0 +1,18 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: frontend
+  labels:
+    app: guestbook
+    tier: frontend
+spec:
+  # comment or delete the following line if you want to use a LoadBalancer
+  type: NodePort 
+  # if your cluster supports it, uncomment the following to automatically create
+  # an external load-balanced IP for the frontend service.
+  # type: LoadBalancer
+  ports:
+  - port: 80
+  selector:
+    app: guestbook
+    tier: frontend