chore: Update google-closure-compiler to the latest version 🚀 (#3765)

## The devDependency [google-closure-compiler](https://github.com/google/closure-compiler-npm) was updated from `20180910.1.0` to `20181008.0.0`.
This version is **not covered** by your **current version range**.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

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[Find out more about this release](https://github.com/google/closure-compiler-npm).

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package-lock.json

@@ -81,7 +81,7 @@
     "fibers": "^3.0.0",
     "fs-extra": "^7.0.0",
     "glob": "^7.1.1",
-    "google-closure-compiler": "^20180910.0.0",
+    "google-closure-compiler": "^20181008.0.0",
     "handlebars": "^4.0.11",
     "htmllint-cli": "0.0.7",
     "husky": "^1.1.1",