build(deps-dev): bump css-loader from 5.2.0 to 6.7.1

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 5.2.0 to 6.7.1.
- [Release notes](https://github.com/webpack-contrib/css-loader/releases)
- [Changelog](https://github.com/webpack-contrib/css-loader/blob/master/CHANGELOG.md)
- [Commits](webpack/css-loader@v5.2.0...v6.7.1)

---
updated-dependencies:
- dependency-name: css-loader
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

package-lock.json

@@ -53,7 +53,7 @@
     "babel-loader": "^8.2.2",
     "babel-plugin-transform-imports": "^2.0.0",
     "copy-webpack-plugin": "^8.1.0",
-    "css-loader": "^5.2.0",
+    "css-loader": "^6.7.1",
     "css-minimizer-webpack-plugin": "^1.3.0",
     "eslint": "^7.23.0",
     "eslint-config-airbnb": "^18.2.1",