chore(package): update babel-preset-react-app to version 9.1.2

Closes #15

Author: greenkeeper[bot]

package.json

@@ -49,7 +49,7 @@
     "babel-core": "^6.26.3",
     "babel-eslint": "^8.2.6",
     "babel-loader": "^7.1.5",
-    "babel-preset-react-app": "^3.1.2",
+    "babel-preset-react-app": "^9.1.2",
     "babel-runtime": "^6.26.0",
     "cross-env": "^5.2.0",
     "css-loader": "^1.0.0",