Bump the dev-css-sass group across 1 directory with 3 updates

Bumps the dev-css-sass group with 3 updates in the / directory: [autoprefixer](https://github.com/postcss/autoprefixer), [cssnano](https://github.com/cssnano/cssnano) and [sass](https://github.com/sass/dart-sass).


Updates `autoprefixer` from 10.4.20 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@10.4.20...10.4.21)

Updates `cssnano` from 7.0.6 to 7.0.7
- [Release notes](https://github.com/cssnano/cssnano/releases)
- [Commits](https://github.com/cssnano/cssnano/compare/cssnano@7.0.6...cssnano@7.0.7)

Updates `sass` from 1.85.1 to 1.87.0
- [Release notes](https://github.com/sass/dart-sass/releases)
- [Changelog](https://github.com/sass/dart-sass/blob/main/CHANGELOG.md)
- [Commits](sass/dart-sass@1.85.1...1.87.0)

---
updated-dependencies:
- dependency-name: autoprefixer
  dependency-version: 10.4.21
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: dev-css-sass
- dependency-name: cssnano
  dependency-version: 7.0.7
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: dev-css-sass
- dependency-name: sass
  dependency-version: 1.87.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: dev-css-sass
...

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Author: dependabot[bot]