[FIX] account: display payment term partial invoice

When having a payment terms with several lines,
the payment term lines are not displayed when
printing the invoice if this one has been
partially paid.

opw-3482256

closes odoo/odoo#133934

Signed-off-by: de Wouters de Bouchout Jean-Benoît (jbw) <jbw@odoo.com>