fix(ssl): delete ssl certificates mounted to mailserver service and move it to caddy

docker-compose.yml

@@ -21,8 +21,6 @@ services:
       - HTTPS=${HTTPS}
     volumes:
       - mailserver_data:/data
-      - ${SSL_CERT_PATH}:/data/ssl/server.crt:ro
-      - ${SSL_KEY_PATH}:/data/ssl/server.key:ro
     logging:
       driver: "json-file"
       options: