Even when applying the --allow_remote_gui_rpc in the docker compose file the container will always generate a remote_host.cfg in the container presumably because the enviroment variable BOINC_REMOTE_HOST is always set inside the container to localhost.
While its possible to overwrite the enviroment variable its not possible to remove it so the start-boinc.sh entrypoint script will always create the remote_host.cfg file overwriting the --allow_remote_gui_rpc cmd option