trade: customize packing list worklist for psa buce:

Purchase Orders are created in draft state and must be confirmed by psa user

bt5/erp5_trade/WorkflowTemplateItem/portal_workflow/packing_list_workflow/worklists/01_draft_purchase_packing_list_list.xml

@@ -10,6 +10,10 @@
             <key> <string>actbox_category</string> </key>
             <value> <string>global</string> </value>
         </item>
+        <item>
+            <key> <string>actbox_icon</string> </key>
+            <value> <string></string> </value>
+        </item>
         <item>
             <key> <string>actbox_name</string> </key>
             <value> <string>Purchase Packing List to Confirm (%(count)s)</string> </value>
@@ -55,6 +59,8 @@ purchase_packing_list_module/view?simulation_state=draft&portal_type=Purchase+Pa
             <key> <string>roles</string> </key>
             <value>
               <tuple>
+                <string>Assignor</string>
+                <string>Assignee</string>
                 <string>Owner</string>
               </tuple>
             </value>