Fix doctrine error after upgrade

Error:
It's a requirement to specify a Metadata Driver and pass it
to Doctrine\ORM\Configuration::setMetadataDriverImpl().

src/CoreBundle/Resources/config/services.yml

@@ -119,13 +119,13 @@ services:
         class: Chamilo\CoreBundle\Entity\Listener\CourseListener
         arguments: ['@chamilo_course.tool_chain', '@chamilo.settings.manager']
         tags:
-            - {name: doctrine.orm.entity_listener}
+            - {name: doctrine.orm.entity_listener, entity_manager: default, lazy: true}
 
     # When Session entity is loaded
     chamilo_core.listener.session:
         class: Chamilo\CoreBundle\Entity\Listener\SessionListener
         tags:
-            - {name: doctrine.orm.entity_listener}
+            - {name: doctrine.orm.entity_listener, entity_manager: default, lazy: true}
 
     # Setting user and platform locale
     chamilo_core.listener.legacy: