chore(package): update eslint-config-react-app to version 3.0.3

Closes #149

Author: greenkeeper[bot]

package.json

@@ -65,7 +65,7 @@
     "enzyme": "^3.1.0",
     "enzyme-adapter-react-16": "^1.0.4",
     "eslint": "^5.0.0",
-    "eslint-config-react-app": "^2.0.0",
+    "eslint-config-react-app": "^3.0.3",
     "eslint-plugin-flowtype": "^2.33.0",
     "eslint-plugin-import": "^2.2.0",
     "eslint-plugin-jsx-a11y": "^6.0.3",