ERP5Workflow: use ListField for destination state in Transition view

+ rename field my_destination_title to my_destination to avoid using magic

bt5/erp5_workflow/SkinTemplateItem/portal_skins/erp5_workflow/Transition_view.xml

@@ -90,12 +90,12 @@
                         <string>my_id</string>
                         <string>my_reference</string>
                         <string>my_title</string>
-                        <string>my_destination_title</string>
                         <string>my_actbox_name</string>
                         <string>my_actbox_url</string>
                         <string>my_actbox_icon</string>
                         <string>my_actbox_category</string>
                         <string>my_trigger_type</string>
+                        <string>my_destination</string>
                       </list>
                     </value>
                 </item>