[Fix] Close ncat server when error occurs to prevent uninterrupted test

tests/runner.bats

@@ -46,7 +46,12 @@ send_request() (
 
 	ncat --listen --unixsock "${deployer_sock}" &
   "${runner_bin}" --conf="${conf_file}" --errs="${errs_file}" \
-    --daemon --stop --verbose || return $?
+    --daemon --stop --verbose
+	code=$?
+	if [ "${code}" -ne 0 ]; then
+		echo "fail" | ncat --unixsock "${deployer_sock}"
+		return "${code}"
+	fi
   (
     inotifywait --quiet --quiet --event create "${response_sock_dir}"
     echo "${request}" | ncat --unixsock "${runner_sock}"