Your requirements could not be resolved to an installable set of packages.
Problem 1
- Root composer.json requires pantheon-systems/wpunit-helpers dev-project-update-info, found pantheon-systems/wpunit-helpers[dev-main, v1.0.0, v1.0.1, v1.x-dev, v2.0.0, v2.x-dev] but it does not match the constraint.