[FIX] stock_dropshipping: test_lifo_price

Because the picking_type of the new move was defined as 
show_operations=True, the quantity_done field on the lines was readonly.

addons/stock_dropshipping/tests/test_lifo_price.py

@@ -77,6 +77,7 @@ class TestLifoPrice(ValuationReconciliationTestCommon):
         purchase_order_lifo2.picking_ids[0].button_validate()
 
         # Let us send some goods
+        self.company_data['default_warehouse'].out_type_id.show_operations = False
         out_form = Form(self.env['stock.picking'])
         out_form.picking_type_id = self.company_data['default_warehouse'].out_type_id
         out_form.immediate_transfer = True