[FIX] account: invoice has not the same currency as the purchase order
[FIX] account: invoice has not the same currency as the purchase order

Used case:

-Configure company in EUR, and user in multi-currency
-Create a purchase order in USD and confirm it
-Click on the smart button "0 invoices" then click on "create"

Result before the fix:

The system created an invoice in EUR, currency of the company,
instead of in USD, currency of the purchase order.

Result after the fix:

The system created an invoice in USD, the currency of the related purchase order.

opw:677568

dfang/odoo,dfang/odoo,laslabs/odoo,storm-computers/odoo,microcom/odoo,ygol/odoo,microcom/odoo,bplancher/odoo,Elico-Corp/odoo_OCB,Elico-Corp/odoo_OCB,ygol/odoo,laslabs/odoo,microcom/odoo,Elico-Corp/odoo_OCB,dfang/odoo,ygol/odoo,laslabs/odoo,laslabs/odoo,hip-odoo/odoo,storm-computers/odoo,microcom/odoo,storm-computers/odoo,hip-odoo/odoo,dfang/odoo,hip-odoo/odoo,storm-computers/odoo,microcom/odoo,bplancher/odoo,bplancher/odoo,bplancher/odoo,ygol/odoo,ygol/odoo,ygol/odoo,laslabs/odoo,Elico-Corp/odoo_OCB,storm-computers/odoo,storm-computers/odoo,bplancher/odoo,Elico-Corp/odoo_OCB,microcom/odoo,hip-odoo/odoo,dfang/odoo,bplancher/odoo,ygol/odoo,hip-odoo/odoo,dfang/odoo,hip-odoo/odoo,Elico-Corp/odoo_OCB,laslabs/odoo