Bump the twentytwentyone-stylelint group across 1 directory with 3 updates

Bumps the twentytwentyone-stylelint group with 3 updates in the /src/wp-content/themes/twentytwentyone directory: [@wordpress/stylelint-config](https://github.com/WordPress/gutenberg/tree/HEAD/packages/stylelint-config), [stylelint](https://github.com/stylelint/stylelint) and [stylelint-config-recommended-scss](https://github.com/stylelint-scss/stylelint-config-recommended-scss).


Updates `@wordpress/stylelint-config` from 21.30.0 to 23.17.0
- [Release notes](https://github.com/WordPress/gutenberg/releases)
- [Changelog](https://github.com/WordPress/gutenberg/blob/trunk/packages/stylelint-config/CHANGELOG.md)
- [Commits](https://github.com/WordPress/gutenberg/commits/@wordpress/stylelint-config@23.17.0/packages/stylelint-config)

Updates `stylelint` from 14.16.1 to 16.21.0
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/main/CHANGELOG.md)
- [Commits](stylelint/stylelint@14.16.1...16.21.0)

Updates `stylelint-config-recommended-scss` from 14.1.0 to 15.0.1
- [Release notes](https://github.com/stylelint-scss/stylelint-config-recommended-scss/releases)
- [Changelog](https://github.com/stylelint-scss/stylelint-config-recommended-scss/blob/master/CHANGELOG.md)
- [Commits](stylelint-scss/stylelint-config-recommended-scss@v14.1.0...v15.0.1)

---
updated-dependencies:
- dependency-name: "@wordpress/stylelint-config"
  dependency-version: 23.17.0
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: twentytwentyone-stylelint
- dependency-name: stylelint
  dependency-version: 16.21.0
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: twentytwentyone-stylelint
- dependency-name: stylelint-config-recommended-scss
  dependency-version: 15.0.1
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: twentytwentyone-stylelint
...

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Author: dependabot[bot]