slapos_cloud: Minor change

Set "value" cause some overprocessing in this case (which breaks some tests when invoked under superuser)

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

@@ -53,7 +53,7 @@ delivery_line = delivery.newContent(
 delivery_line.edit(
               price=0.0,
               quantity=1.0,
-              aggregate_value=context)
+              aggregate=context.getRelativeUrl())
 
 
 delivery.confirm()