chore(package): update prettier to version 2.0.4

Closes #59

Author: greenkeeper[bot]

package.json

@@ -67,7 +67,7 @@
     "jest": "^23.6.0",
     "lerna": "^3.4.0",
     "postcss-load-config": "^2.0.0",
-    "prettier": "^1.14.3"
+    "prettier": "^2.0.4"
   },
   "workspaces": [
     "packages/*"