fix(package): update react to version 16.8.4

Author: greenkeeper[bot]

package.json

@@ -29,7 +29,7 @@
     "bootstrap": "4.3.1",
     "oclazyload": "1.1.0",
     "prop-types": "15.7.2",
-    "react": "16.8.3",
+    "react": "16.8.4",
     "react-dom": "16.8.3"
   },
   "devDependencies": {