chore: Bump flutter_screenutil from 5.5.4 to 5.6.1

Bumps [flutter_screenutil](https://github.com/OpenFlutter/flutter_screenutil) from 5.5.4 to 5.6.1.
- [Release notes](https://github.com/OpenFlutter/flutter_screenutil/releases)
- [Changelog](https://github.com/OpenFlutter/flutter_screenutil/blob/master/CHANGELOG.md)
- [Commits](https://github.com/OpenFlutter/flutter_screenutil/commits)

---
updated-dependencies:
- dependency-name: flutter_screenutil
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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