Add servicemanager to Barcode's composer.json

`zendframework/zend-servicemanager` is a required dependency for the Barcode component and it is missing from its `composer.json`.

This PR add the required dependency.

The related error is:
`Fatal error: Class 'Zend\ServiceManager\AbstractPluginManager' not found in /project/vendor/zendframework/zend-barcode/Zend/Barcode/ObjectPluginManager.php on line 22`