Explain your ip address when visiting an appliation by trait

[zzxwill]

In the doc, users are asked to visit the application by the following command https://kubevela.io/zh/docs/next/quick-start#%E4%B8%80%E4%B8%AA%E6%9C%80%E7%AE%80%E5%8D%95%E7%9A%84%E7%A4%BA%E4%BE%8B, while your ip address is not well documented.
$ curl -H "Host:testsvc.example.com" http://<your ip address>/

You can see the endpoint or address of your ingress. By getting it, you can direct users to visit the console of a cloud provider or by listing the ingress ojbect.

➜  kubevela.io git:(main) kubectl get ingress
NAME             CLASS    HOSTS                 ADDRESS         PORTS   AGE
express-server   <none>   testsvc.example.com   8.210.233.186   80      13m

[zzxwill]

If there is an Ingress backend, you can visit the webapp by the domain.

➜  demo-1015 vela status first-vela-app
I1015 12:15:30.127161   40740 request.go:665] Waited for 1.012574189s due to client-side throttling, not priority and fairness, request: GET:https://47.242.250.36:6443/apis/apiextensions.k8s.io/v1?timeout=32s
About:

  Name:      	first-vela-app
  Namespace: 	default
  Created at:	2021-10-15 11:58:13 +0800 CST

Services:

  - Name: express-server
    Type: webservice
    NOT DIAGNOSED
    Traits:
      - ✅ ingress-1-20: Visiting URL: poc.c8cf3e761a86746c9ad1f054282232604.cn-hongkong.alicontainer.com, IP: 8.210.233.186
    Last Deployment:
      Created at: 2021-10-15 11:58:13 +0800 CST

➜  demo-1015 curl poc.c8cf3e761a86746c9ad1f054282232604.cn-hongkong.alicontainer.com
<pre>
Hello World


                                       ##         .
                                 ## ## ##        ==
                              ## ## ## ## ##    ===
                           /""""""""""""""""\___/ ===
                      ~~~ {~~ ~~~~ ~~~ ~~~~ ~~ ~ /  ===- ~~~
                           \______ o          _,/
                            \      \       _,'
                             `'--.._\..--''
</pre>

[wonderflow]

I'm not quite get what we should do in this issue. Would you like to send a pull request to refine it? @zzxwill

[zzxwill]

People might not know what is your ip address. I was opening an issue as good first issue, intending someone to fix it.