Add picked step to customer shipment workflow

issue9634
review329071002

tests/scenario_sale_shipment_grouping.rst

@@ -153,6 +153,7 @@ Check the shipments::
     2
     >>> for shipment in shipments:
     ...     _ = shipment.click('assign_try')
+    ...     shipment.click('pick')
     ...     shipment.click('pack')
     ...     shipment.click('done')