build(deps): bump postcss, css-loader and vue-loader

Bumps [postcss](https://github.com/postcss/postcss) to 8.4.33 and updates ancestor dependencies [postcss](https://github.com/postcss/postcss), [css-loader](https://github.com/webpack-contrib/css-loader) and [vue-loader](https://github.com/vuejs/vue-loader). These dependencies need to be updated together.


Updates `postcss` from 5.2.17 to 8.4.33
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@5.2.17...8.4.33)

Updates `css-loader` from 0.28.11 to 6.9.0
- [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@v0.28.11...v6.9.0)

Updates `vue-loader` from 13.7.1 to 17.4.2
- [Release notes](https://github.com/vuejs/vue-loader/releases)
- [Changelog](https://github.com/vuejs/vue-loader/blob/main/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vue-loader/commits/v17.4.2)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: indirect
- dependency-name: css-loader
  dependency-type: direct:development
- dependency-name: vue-loader
  dependency-type: direct:development
...

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