chore(package): update eslint-plugin-prettier to version 3.1.0

Closes #19

Author: greenkeeper[bot]

package.json

@@ -49,7 +49,7 @@
     "cross-env": "^5.2.0",
     "eslint": "^5.3.0",
     "eslint-config-prettier": "^3.0.0",
-    "eslint-plugin-prettier": "^2.6.2",
+    "eslint-plugin-prettier": "^3.1.0",
     "mocha": "^6.0.0",
     "nyc": "^12.0.2",
     "prettier": "^1.14.0",