chore(deps-dev): update phpunit/phpunit requirement
chore(deps-dev): update phpunit/phpunit requirement

Updates the requirements on [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) to permit the latest version.
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/master/ChangeLog-9.2.md)
- [Commits](https://github.com/sebastianbergmann/phpunit/compare/9.2.5...9.2.6)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
neilime/zf-twbs-helper-module,neilime/zf-twbs-helper-module