build(deps): bump postcss, autoprefixer, css-loader, postcss-import, …

…postcss-loader, postcss-url and vue-loader

Bumps [postcss](https://github.com/postcss/postcss) to 8.4.20 and updates ancestor dependencies [postcss](https://github.com/postcss/postcss), [autoprefixer](https://github.com/postcss/autoprefixer), [css-loader](https://github.com/webpack-contrib/css-loader), [postcss-import](https://github.com/postcss/postcss-import), [postcss-loader](https://github.com/webpack-contrib/postcss-loader), [postcss-url](https://github.com/postcss/postcss-url) and [vue-loader](https://github.com/vuejs/vue-loader). These dependencies need to be updated together.


Updates `postcss` from 5.2.18 to 8.4.20
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/commits/8.4.20)

Updates `autoprefixer` from 7.2.6 to 10.4.13
- [Release notes](https://github.com/postcss/autoprefixer/releases)
- [Changelog](https://github.com/postcss/autoprefixer/blob/main/CHANGELOG.md)
- [Commits](postcss/autoprefixer@7.2.6...10.4.13)

Updates `css-loader` from 0.28.11 to 6.7.3
- [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...v6.7.3)

Updates `postcss-import` from 11.1.0 to 15.1.0
- [Release notes](https://github.com/postcss/postcss-import/releases)
- [Changelog](https://github.com/postcss/postcss-import/blob/master/CHANGELOG.md)
- [Commits](postcss/postcss-import@11.1.0...15.1.0)

Updates `postcss-loader` from 2.1.6 to 7.0.2
- [Release notes](https://github.com/webpack-contrib/postcss-loader/releases)
- [Changelog](https://github.com/webpack-contrib/postcss-loader/blob/master/CHANGELOG.md)
- [Commits](webpack-contrib/postcss-loader@v2.1.6...v7.0.2)

Updates `postcss-url` from 7.3.2 to 10.1.3
- [Release notes](https://github.com/postcss/postcss-url/releases)
- [Changelog](https://github.com/postcss/postcss-url/blob/master/CHANGELOG.md)
- [Commits](postcss/postcss-url@7.3.2...10.1.3)

Updates `vue-loader` from 13.7.3 to 17.0.1
- [Release notes](https://github.com/vuejs/vue-loader/releases)
- [Changelog](https://github.com/vuejs/vue-loader/blob/next/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vue-loader/commits/v17.0.1)

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

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