slapos_cloud: do not crash if no instance is found

master/bt5/slapos_cloud/SkinTemplateItem/portal_skins/slapos_cloud/ComputePartition_propagateRemoteNode.py

@@ -20,11 +20,11 @@ if compute_partition.getId() == 'SHARED_REMOTE':
   )
 
 else:
-  local_instance_list = [portal.portal_catalog.getResultValue(
+  local_instance_list = portal.portal_catalog(
     portal_type='Software Instance',
     aggregate__uid=compute_partition.getUid(),
     validation_state='validated'
-  )]
+  )
 
 for local_instance in local_instance_list: