Sale order invoiced fix

Casuistry that corrects this module:

Sales order with more than one line and at least one of them with a product of service type or a description without product. This order has order policy "On delivery order". When the stock picking is generated, it is partially transferred in more than one stock picking and, subsequently, those invoices are invoiced at the same time, the invoices are generated correctly.

But if we now cancel the invoices and re-generate them from the stock pickings, the product service lines or without product are duplicated, since they appear in all the generated invoices. That is, the first time you invoice there is no error, but the following ones.

This module is responsible for solving the error committed by the "_fnct_line_invoiced" function that calculates the "invoiced" field. For this we calculate the value of the "invoiced" field from another function that corrects it.