chore(package): update prettier to version 2.0.4

Closes #276

Author: greenkeeper[bot]

package.json

@@ -51,7 +51,7 @@
     "lint-staged": "^9.0.0",
     "npm-check-updates": "^2.14.3",
     "p-series": "^2.1.0",
-    "prettier": "^1.15.2",
+    "prettier": "^2.0.4",
     "rimraf": "^2.6.2",
     "size-limit": "^1.0.1",
     "webpack": "^4.26.0"