chore(package): update prettier to version 2.0.4

Closes #77

Author: greenkeeper[bot]

package.json

@@ -40,7 +40,7 @@
     "@types/tape": "^4.2.33",
     "assemblyscript": "^0.8.1",
     "gulp": "^4.0.2",
-    "prettier": "^1.18.2",
+    "prettier": "^2.0.4",
     "scout.ts": "0.0.2",
     "tape": "^4.11.0",
     "ts-node": "^8.4.1",