chore(package): update prettier to version 2.0.4

Closes #75

Author: greenkeeper[bot]

Diff for: package.json

@@ -52,7 +52,7 @@
         "eslint-plugin-react": "~7.10.0",
         "lint-staged": "^7.0.3",
         "mocha": "^5.0.5",
-        "prettier": "^1.11.1"
+        "prettier": "^2.0.4"
     },
     "peerDependencies": {
         "eslint": "^5.0.1",