[pso-server] Run Docker image in isolated mode

[ProtossGP32]

DESCRIPTION: Right now in order for the server to be reachable through local network the docker container must be run with --network=host option. I've tried instead to expose only the relevant ports to GameCube connections during my tests but the client never reaches the server.

TASK: Ensure that the Docker container can run using its own network and exposing the bare minimum of ports for it to accept client connections