Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /var/www/html/drupal/vendor/chi-teck/drupal-code-generator/src/Test/GeneratorTest.php:20 Stack trace: #0 {main} thrown in /var/www/html/drupal/vendor/chi-teck/drupal-code-generator/src/Test/GeneratorTest.php on line 20