add react-intersection-observer dependency

Author: maerzhase

package-lock.json

@@ -61,5 +61,8 @@
     "trailingComma": "all",
     "singleQuote": true,
     "arrowParens": "avoid"
+  },
+  "dependencies": {
+    "react-intersection-observer": "^8.31.0"
   }
 }