Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires phpunit/phpunit ^12.0-dev -> satisfiable by phpunit/phpunit[12.0.x-dev (alias of dev-main)]. - phpunit/phpunit dev-main requires phpunit/php-file-iterator ^5.1.0 -> found phpunit/php-file-iterator[5.1.0, 5.1.x-dev] but it conflicts with your root composer.json require (^6.0-dev). - phpunit/phpunit 12.0.x-dev is an alias of phpunit/phpunit dev-main and thus requires it to be installed too.

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