chore(deps-dev): bump the all group across 1 directory with 2 updates (#819)

Bumps the all group with 2 updates in the /site directory: [autoprefixer](https://github.com/postcss/autoprefixer) and [postcss](https://github.com/postcss/postcss).


Updates `autoprefixer` from 10.4.27 to 10.5.0
- [Release notes](https://github.com/postcss/autoprefixer/releases)
- [Changelog](https://github.com/postcss/autoprefixer/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/autoprefixer/compare/10.4.27...10.5.0)

Updates `postcss` from 8.5.8 to 8.5.10
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.5.8...8.5.10)

---
updated-dependencies:
- dependency-name: autoprefixer
  dependency-version: 10.5.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: all
- dependency-name: postcss
  dependency-version: 8.5.10
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: all
...

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