Bump postcss, autoprefixer, postcss-assets, postcss-cli and postcss-inline-svg

Bumps [postcss](https://github.com/postcss/postcss) to 8.5.5 and updates ancestor dependencies [postcss](https://github.com/postcss/postcss), [autoprefixer](https://github.com/postcss/autoprefixer), [postcss-assets](https://github.com/assetsjs/postcss-assets), [postcss-cli](https://github.com/postcss/postcss-cli) and [postcss-inline-svg](https://github.com/TrySound/postcss-inline-svg). These dependencies need to be updated together.


Updates `postcss` from 7.0.39 to 8.5.5
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@7.0.39...8.5.5)

Updates `autoprefixer` from 9.8.8 to 10.4.21
- [Release notes](https://github.com/postcss/autoprefixer/releases)
- [Changelog](https://github.com/postcss/autoprefixer/blob/main/CHANGELOG.md)
- [Commits](postcss/autoprefixer@9.8.8...10.4.21)

Updates `postcss-assets` from 5.0.0 to 6.0.0
- [Release notes](https://github.com/assetsjs/postcss-assets/releases)
- [Changelog](https://github.com/borodean/postcss-assets/blob/main/CHANGELOG.md)
- [Commits](borodean/postcss-assets@5.0.0...6.0.0)

Updates `postcss-cli` from 7.1.2 to 11.0.1
- [Release notes](https://github.com/postcss/postcss-cli/releases)
- [Changelog](https://github.com/postcss/postcss-cli/blob/master/CHANGELOG.md)
- [Commits](postcss/postcss-cli@7.1.2...11.0.1)

Updates `postcss-inline-svg` from 4.1.0 to 6.0.0
- [Changelog](https://github.com/TrySound/postcss-inline-svg/blob/master/CHANGELOG.md)
- [Commits](TrySound/postcss-inline-svg@v4.1.0...v6.0.0)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.5
  dependency-type: indirect
- dependency-name: autoprefixer
  dependency-version: 10.4.21
  dependency-type: direct:development
- dependency-name: postcss-assets
  dependency-version: 6.0.0
  dependency-type: direct:development
- dependency-name: postcss-cli
  dependency-version: 11.0.1
  dependency-type: direct:development
- dependency-name: postcss-inline-svg
  dependency-version: 6.0.0
  dependency-type: direct:development
...

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Author: dependabot[bot]