site: Add example to ingress tutorial (#20814)

We show how to connect to redis with telnet, so let's show some commands
to make it more interesting.

This is modified example from redis docs:
https://redis.io/docs/latest/develop/get-started/data-store/#store-and-retrieve-data

site/content/en/docs/tutorials/nginx_tcp_udp_ingress.md

@@ -202,6 +202,16 @@ Connected to 192.168.99.179.
 Escape character is '^]'
 ```
 
+You can chat with the redis service:
+
+```text
+SET minikube:1 "it works!"
++OK
+GET minikube:1
+$9
+it works!
+```
+
 To exit telnet enter the `Ctrl` key and `]` at the same time. Then type `quit` and press enter.
 
 If you were not able to connect please review your steps above.