Connection.php

<?php

namespace Drupal\driver_test\Driver\Database\DrivertestMysql;

include_once dirname(__DIR__, 8) . '/mysql/src/Driver/Database/mysql/Connection.php';
use Drupal\mysql\Driver\Database\mysql\Connection as CoreConnection;

/**
 * MySQL test implementation of \Drupal\Core\Database\Connection.
 */
class Connection extends CoreConnection {
    
    /**
     * {@inheritdoc}
     */
    public function driver() {
        return 'DrivertestMysql';
    }

}