gluetun: enable auth for control server

[0xlua]

Since gluetun v3.39.1 accessing the control server requires that an auth method has been set. Either through an environment variable or through a toml config file. The file allows for a more fine grained access control, so this method is preferred. See below for some examples.

API Keys can be generated with docker run --rm qmcgaw/gluetun genkey. I have to adapt this to podman.

1. Checking Status & Public IP

[[roles]]
name = "check status"
routes = ["GET /v1/publicip/ip", "GET /v1/vpn/status"]
auth = "apikey"
apikey = "myapikey"

2. Set Deluge Incoming Ports (see #197)

[[roles]]
name = "deluge"
routes = ["GET /v1/portforward"]
auth = "apikey"
apikey = "myapikey"