chore(deps): update dependency prettier to v1.18.0

Author: renovate-bot

package-lock.json

@@ -38,7 +38,7 @@
     "mocha": "6.1.4",
     "npm-run-all": "4.1.5",
     "phantomjs-prebuilt": "2.1.16",
-    "prettier": "1.17.1",
+    "prettier": "1.18.0",
     "rollup": "1.13.1",
     "rollup-plugin-commonjs": "10.0.0",
     "rollup-plugin-json": "4.0.0",