slapos_upgrader: simplify

master/bt5/slapos_upgrader/SkinTemplateItem/portal_skins/slapos_upgrader/ComputeNode_triggerObjectMigrationToVirtualMaster.py

@@ -29,9 +29,10 @@ if len(category_list) != len(new_category_list):
   compute_node.setCategoryList(new_category_list)
 
 # Trigger migrations of related objects
-for sql_object in portal.portal_catalog(
+portal.portal_catalog.searchAndActivate(
+  method_id='Base_activateObjectMigrationToVirtualMaster',
+  method_args=[project_relative_url],
+
   portal_type='Software Installation',
   aggregate__uid=compute_node.getUid()
-):
-  relative_url_to_migrate = sql_object.getObject().getRelativeUrl()
-  sql_object.getObject().activate(serialization_tag='Person_checkSiteMigrationCreatePersonalVirtualMaster_%s' % relative_url_to_migrate).Base_activateObjectMigrationToVirtualMaster(project_relative_url)
+)