Bump friendsofphp/php-cs-fixer from 3.8.0 to 3.20.0

Bumps [friendsofphp/php-cs-fixer](https://github.com/FriendsOfPHP/PHP-CS-Fixer) from 3.8.0 to 3.20.0.
- [Release notes](https://github.com/FriendsOfPHP/PHP-CS-Fixer/releases)
- [Changelog](https://github.com/PHP-CS-Fixer/PHP-CS-Fixer/blob/master/CHANGELOG.md)
- [Commits](PHP-CS-Fixer/PHP-CS-Fixer@v3.8.0...v3.20.0)

---
updated-dependencies:
- dependency-name: friendsofphp/php-cs-fixer
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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