Your requirements could not be resolved to an installable set of packages.
Problem 1
- Root composer.json requires phpunit/phpunit ^12.0 -> satisfiable by phpunit/phpunit[12.0.0, ..., 12.2.x-dev].
- phpunit/phpunit[12.0.0, ..., 12.2.x-dev] require php >=8.3 -> your php version (8.1.32) does not satisfy that requirement.