build(deps-dev): bump css-loader in /superset-frontend

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 6.8.1 to 7.1.2.
- [Release notes](https://github.com/webpack-contrib/css-loader/releases)
- [Changelog](https://github.com/webpack-contrib/css-loader/blob/master/CHANGELOG.md)
- [Commits](webpack-contrib/css-loader@v6.8.1...v7.1.2)

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

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