Gluetun web api

[emanuellopes]

Is your feature request related to a problem?

There is a way to allow define a custom port to access to gluetun http Portal.
This will allow to add the gluetun rest api in uptime kuma and monitorize if vpn is down or up.

Describe the solution you'd like

Allow define a custom port when we add the gluetun vpn in our container.

Documentation:
https://github.com/qdm12/gluetun-wiki/blob/main/setup/options/control-server.md
https://github.com/qdm12/gluetun-wiki/blob/main/setup/advanced/control-server.md

Describe alternatives you've considered

N/A

Additional context

No response

I've read and agree with the following

• I've checked all open and closed issues and my request is not there.
• I've checked all open and closed pull requests and my request is not there.