Set invoice progress of shipment cost line of sale always as 100%

Closes #13160

modules/sale_shipment_cost/sale.py

@@ -436,6 +436,13 @@ class Line(metaclass=PoolMeta):
                         shipment_cost_invoiced.append(shipment.id)
         return lines
 
+    @property
+    def _invoice_remaining_quantity(self):
+        quantity = super()._invoice_remaining_quantity
+        if self.shipment_cost is not None:
+            quantity = 0
+        return quantity
+
     def _get_invoice_line_quantity(self):
         quantity = super()._get_invoice_line_quantity()
         if self.shipment_cost is not None:

modules/sale_shipment_cost/tests/scenario_sale_shipment_cost.rst

@@ -127,6 +127,8 @@ Sale products with cost on shipment::
     1.0
     >>> cost_line.amount
     Decimal('3.00')
+    >>> cost_line.invoice_progress
+    1.0
     >>> sale.click('confirm')
     >>> sale.click('process')
     >>> sale.state
@@ -211,6 +213,8 @@ Sale products with cost on order::
     1.0
     >>> cost_line.amount
     Decimal('3.00')
+    >>> cost_line.invoice_progress
+    1.0
     >>> sale.click('confirm')
     >>> sale.click('process')
     >>> sale.state