The job was canceled because "ubuntu-latest_7_0" failed.

Your requirements could not be resolved to an installable set of packages. Problem 1 - phpunit/phpunit[7.5.0, ..., 7.5.20] require php ^7.1 -> your php version (5.6.40) does not satisfy that requirement. - phpunit/phpunit[8.5.0, ..., 8.5.11] require php ^7.2 -> your php version (5.6.40) does not satisfy that requirement. - phpunit/phpunit[8.5.12, ..., 8.5.33] require php >=7.2 -> your php version (5.6.40) does not satisfy that requirement. - yoast/phpunit-polyfills 2.0.0 requires phpunit/phpunit ^5.7.21 || ^6.0 || ^7.0 || ^8.0 || ^9.0 || ^10.0 -> satisfiable by phpunit/phpunit[7.5.0, ..., 7.5.20, 8.5.0, ..., 8.5.33]. - Root composer.json requires yoast/phpunit-polyfills ^2.0 -> satisfiable by yoast/phpunit-polyfills[2.0.0].