[FIX] account, usabilty: add form mode to action open.
[FIX] account, usabilty: add form mode to action open.

This fix allows users to view the form of the invoices they accessed through the payments (via the 'invoices' button)

ygol/odoo,hip-odoo/odoo,dfang/odoo,hip-odoo/odoo,hip-odoo/odoo,ygol/odoo,hip-odoo/odoo,ygol/odoo,dfang/odoo,dfang/odoo,ygol/odoo,ygol/odoo,hip-odoo/odoo,hip-odoo/odoo,ygol/odoo,ygol/odoo,dfang/odoo,dfang/odoo,dfang/odoo