Fixed error if config section is empty

Instead of the exception I got this:
Recoverable Error
Argument 2 passed to Kdyby\Doctrine\DI\OrmExtension::processEntityManager() must be of the type array, boolean given, called in E:\Media33\m33\deployer\vendor\kdyby\doctrine\src\Kdyby\Doctrine\DI\OrmExtension.php on line 158 and defined