chore(package): update eslint-plugin-prettier to version 3.1.1

Closes #9

Author: greenkeeper[bot]

package.json

@@ -46,7 +46,7 @@
     "babel-preset-env": "1.7.0",
     "eslint": "^5.3.0",
     "eslint-config-prettier": "^3.0.0",
-    "eslint-plugin-prettier": "^2.6.2",
+    "eslint-plugin-prettier": "^3.1.1",
     "greenkeeper-lockfile": "1.15.1",
     "heroku": "^7.7.8",
     "jest": "23.5.0",