Check only shipment with cost method 'order' to invoice shipment cost on order

If the sale is linked to a shipment with a different cost method than order,
it should not be considered to decide to invoice or not the sale shipment
cost.

Closes #13171

modules/sale_shipment_cost/sale.py

@@ -450,7 +450,8 @@ class Line(metaclass=PoolMeta):
                 quantity = 0
             elif (self.sale.shipment_cost_method == 'order'
                     and self.sale.invoice_method == 'shipment'):
-                shipments = self.sale.shipments
+                shipments = [
+                    s for s in self.sale.shipments if s.cost_method == 'order']
                 if (not shipments
                         or all(s.state != 'done' for s in shipments)):
                     quantity = 0