Bump the twentytwentyone-stylelint group

Bumps the twentytwentyone-stylelint group in /src/wp-content/themes/twentytwentyone with 2 updates: [@wordpress/stylelint-config](https://github.com/WordPress/gutenberg/tree/HEAD/packages/stylelint-config) and [stylelint](https://github.com/stylelint/stylelint).


Updates `@wordpress/stylelint-config` from 21.30.0 to 23.25.0
- [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/[email protected]/packages/stylelint-config)

Updates `stylelint` from 14.16.1 to 16.25.0
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/main/CHANGELOG.md)
- [Commits](stylelint/stylelint@14.16.1...16.25.0)

---
updated-dependencies:
- dependency-name: "@wordpress/stylelint-config"
  dependency-version: 23.25.0
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: twentytwentyone-stylelint
- dependency-name: stylelint
  dependency-version: 16.25.0
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: twentytwentyone-stylelint
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]