Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires silverstripe/cms ^6 -> satisfiable by silverstripe/cms[6.x-dev]. - phpunit/phpunit 11.4.x-dev is an alias of phpunit/phpunit dev-main and thus requires it to be installed too. - phpunit/phpunit[dev-main, 11.3.0, ..., 11.3.5] require sebastian/diff ^6.0.2 -> satisfiable by sebastian/diff[6.0.2, 6.0.x-dev]. - Conclusion: don't install sebastian/diff 6.0.2 (conflict analysis result) - Root composer.json requires phpunit/phpunit ^11.3 -> satisfiable by phpunit/phpunit[11.3.0, ..., 11.4.x-dev (alias of dev-main)].

Process completed with exit code 2.

The following actions use a deprecated Node.js version and will be forced to run on node20: actions/checkout@8e5e7e5ab8b370d6c329ec480221332ada57f0ab, shivammathur/setup-php@1a18b2267f80291a81ca1d33e7c851fe09e7dfc4, actions/cache@88522ab9f39a2ea568f7027eddc7d8d8bc9d59c8, actions/upload-artifact@0b7f8abb1508181956e8e162db84b466c27e18ce. For more info: https://github.blog/changelog/2024-03-07-github-actions-all-actions-will-run-on-node20-instead-of-node16-by-default/