Update package in StackBlitz demo to current version

Author: Oblosys

examples/parent-child-demo/package.json

@@ -15,6 +15,6 @@
     "react": "16.8.6",
     "react-dom": "16.8.6",
     "react-hot-loader": "4.11.1",
-    "react-lifecycle-visualizer": "^2.2.3"
+    "react-lifecycle-visualizer": "^2.2.4"
   }
 }