fix: changing node version on integration tests to 22 (#698)

Author: pacostas

integration/testdata/graceful_shutdown_app/package.json

@@ -5,7 +5,7 @@
   },
   "description": "some graceful app",
   "engines": {
-    "node": "~18"
+    "node": "~22"
   },
   "license": "",
   "name": "graceful_shutdown_app",