Update demo dependencies

Author: Oblosys

examples/parent-child-demo/package.json

@@ -15,6 +15,6 @@
     "react": "^16.13.1",
     "react-dom": "^16.13.1",
     "react-hot-loader": "^4.12.21",
-    "react-lifecycle-visualizer": "^2.2.7"
+    "react-lifecycle-visualizer": "^2.2.8"
   }
 }