Enhancements in clarity to access-application-cluster/connecting-frontend-backend.md (#25927)

* Enhancements in clarity to docs/tasks/access-application-cluster/connecting-frontend-backend.md

* Code review comments

* Reverting name of service due to backed value in Dockerimage

content/en/examples/service/access/backend-service.yaml

@@ -0,0 +1,14 @@
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: hello
+spec:
+  selector:
+    app: hello
+    tier: backend
+  ports:
+  - protocol: TCP
+    port: 80
+    targetPort: http
+...