Your requirements could not be resolved to an installable set of packages.
Problem 1
- Root composer.json requires phpunit/phpunit ^12.2.0 -> satisfiable by phpunit/phpunit[12.2.0].
- phpunit/phpunit 12.2.0 requires php >=8.3 -> your php version (8.1.32) does not satisfy that requirement.
Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.