Build(deps-dev): Update ergebnis/phpstan-rules requirement
Build(deps-dev): Update ergebnis/phpstan-rules requirement

Updates the requirements on [ergebnis/phpstan-rules](https://github.com/ergebnis/phpstan-rules) to permit the latest version.
- [Release notes](https://github.com/ergebnis/phpstan-rules/releases)
- [Changelog](https://github.com/ergebnis/phpstan-rules/blob/main/CHANGELOG.md)
- [Commits](https://github.com/ergebnis/phpstan-rules/compare/0.15.0...0.15.1)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
mimmi20/wurfl-generic-request