Fix(judgehost): works with Debian12 + docker

roles/configure_domserver/templates/docker-compose.yml.jinja

@@ -21,8 +21,11 @@ services:
       CONTAINER_TIMEZONE: Asia/Taipei
     restart: always
     volumes:
+      - "restapi_secret:/opt/domjudge/domserver/etc/restapi.secret"
       - "./config/php/domjudge.conf:/etc/php/8.2/fpm/pool.d/domjudge.conf"
     depends_on:
       - mariadb
     ports: 
       - "127.0.0.1:8080:80"
+volumes:
+  restapi_secret: {}