Ticket 47651 - Finaliser to remove instances backups

https://fedorahosted.org/389/ticket/47651

Reviewed by: Nathan Kinder

dirsrvtests/tickets/finalizer.py

@@ -36,6 +36,9 @@ def test_finalizer():
         instance.allocate(args_instance)
         if instance.exists():
             instance.delete()
+            
+        # remove any existing backup for this instance
+        instance.clearBackupFS()
         
 def run_isolated():
     '''