build(deps-dev): bump eslint-plugin-no-unsanitized in /addon (#619)

Bumps [eslint-plugin-no-unsanitized](https://github.com/mozilla/eslint-plugin-no-unsanitized) from 3.1.2 to 3.1.4.
- [Release notes](https://github.com/mozilla/eslint-plugin-no-unsanitized/releases)
- [Commits](https://github.com/mozilla/eslint-plugin-no-unsanitized/commits)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

addon/package-lock.json

@@ -10,7 +10,7 @@
   },
   "devDependencies": {
     "eslint-plugin-mozilla": "^0.9.0",
-    "eslint-plugin-no-unsanitized": "^3.1.2",
+    "eslint-plugin-no-unsanitized": "^3.1.4",
     "web-ext": "^5.1.0",
     "webpack": "^4.44.2",
     "webpack-cli": "^3.3.12"