Bump the dependencies group with 1 update

Bumps the dependencies group with 1 update: [squizlabs/php_codesniffer](https://github.com/PHPCSStandards/PHP_CodeSniffer).


Updates `squizlabs/php_codesniffer` from 3.8.1 to 3.9.0
- [Release notes](https://github.com/PHPCSStandards/PHP_CodeSniffer/releases)
- [Changelog](https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/master/CHANGELOG.md)
- [Commits](PHPCSStandards/PHP_CodeSniffer@3.8.1...3.9.0)

---
updated-dependencies:
- dependency-name: squizlabs/php_codesniffer
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: dependencies
...

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