build(deps-dev): Bump eslint-loader from 3.0.4 to 4.0.0 in /frontend (#487)

Bumps [eslint-loader](https://github.com/webpack-contrib/eslint-loader) from 3.0.4 to 4.0.0.
- [Release notes](https://github.com/webpack-contrib/eslint-loader/releases)
- [Changelog](https://github.com/webpack-contrib/eslint-loader/blob/master/CHANGELOG.md)
- [Commits](webpack-contrib/eslint-loader@v3.0.4...v4.0.0)

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]

frontend/package.json

@@ -30,7 +30,7 @@
     "eslint": "^6.2.2",
     "eslint-config-prettier": "^6.2.0",
     "eslint-config-standard": "^14.1.0",
-    "eslint-loader": "^3.0.0",
+    "eslint-loader": "^4.0.0",
     "eslint-plugin-fetch-options": "0.0.5",
     "eslint-plugin-html": "^6.0.0",
     "eslint-plugin-mozilla": "^2.1.0",