added missed use statement

SerializerBundleAwareInterface.php

@@ -2,7 +2,9 @@
 
 namespace JMS\SerializerBundle;
 
+use JMS\SerializerBundle\DependencyInjection\JMSSerializerExtension;
+
 interface SerializerBundleAwareInterface
 {
     function configureSerializerExtension(JMSSerializerExtension $extension);
-}
+}