fix minikube service list for docker on mac os

[josedonizetti]

mikube service list

|-------------|-----------------|--------------|-------------------------|
|  NAMESPACE  |      NAME       | TARGET PORT  |           URL           |
|-------------|-----------------|--------------|-------------------------|
| default     | hello-minikube1 |              | http://172.17.0.2:30962 |
| default     | kubernetes      | No node port |
| kube-system | kube-dns        | No node port |
|-------------|-----------------|--------------|-------------------------|
❌  Accessing service is not implemented yet for docker driver on Mac.
The following issue is tracking the in progress work::
https://github.com/kubernetes/minikube/issues/6778
💣  Not yet implemented for docker driver on MacOS.

We need to remove the not implemented warning, and the URL must be empty, because we only expose it if the ./minikube service is running, so it would be misleading to display 127.0.0.1:XXXX if it won't work without calling the service cmd.