build(deps-dev): Bump webpack-cli from 3.3.11 to 3.3.12 in /addon (#552)

Bumps [webpack-cli](https://github.com/webpack/webpack-cli) from 3.3.11 to 3.3.12.
- [Release notes](https://github.com/webpack/webpack-cli/releases)
- [Changelog](https://github.com/webpack/webpack-cli/blob/v3.3.12/CHANGELOG.md)
- [Commits](webpack/webpack-cli@v3.3.11...v3.3.12)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Author: dependabot-preview[bot]

addon/package-lock.json

@@ -13,7 +13,7 @@
     "eslint-plugin-no-unsanitized": "^3.1.2",
     "web-ext": "^4.2.0",
     "webpack": "^4.43.0",
-    "webpack-cli": "^3.3.11"
+    "webpack-cli": "^3.3.12"
   },
   "scripts": {
     "lint": "eslint src/*.js",