Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires silverstripe/installer 6.0.x-dev -> satisfiable by silverstripe/installer[6.0.x-dev]. - silverstripe/installer 6.0.x-dev requires silverstripe/vendor-plugin 2.0.x-dev -> found silverstripe/vendor-plugin[2.0.x-dev] but it conflicts with your root composer.json require (^3). Problem 2 - Root composer.json requires silverstripe/assets ^3 -> satisfiable by silverstripe/assets[3.0.0-alpha1, 3.0.x-dev, 3.x-dev]. - silverstripe/assets[3.0.0-alpha1, ..., 3.x-dev] require silverstripe/vendor-plugin ^2 -> found silverstripe/vendor-plugin[2.0.0-alpha1, ..., 2.x-dev] but it conflicts with your root composer.json require (^3).

Process completed with exit code 2.