Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /var/www/usonboard.com/vendor/php-http/discovery/tests/Composer/PluginTest.php:15 Stack trace: #0 {main} thrown in /var/www/usonboard.com/vendor/php-http/discovery/tests/Composer/PluginTest.php on line 15