⬆️ Bump phpunit/phpunit in the composer group

Bumps the composer group with 1 update: [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit).


Updates `phpunit/phpunit` from 12.2.5 to 12.2.6
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/12.2.6/ChangeLog-12.2.md)
- [Commits](sebastianbergmann/phpunit@12.2.5...12.2.6)

---
updated-dependencies:
- dependency-name: phpunit/phpunit
  dependency-version: 12.2.6
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: composer
...

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

Author: dependabot[bot]