[FIX] web: invoice layout

Before this PR, when multi vat was activated and a foreign vat number was set on
 a fiscal position it was not printed on the invoice for the following layout:
 Striped, light and boxed. The Bold layout is not impacted since it does not use
 company details.

 This PR adds the foreign vat on the invoice when it's necessary.

closes odoo/odoo#118782

Task-id: 3248767
Signed-off-by: John Laterre (jol) <jol@odoo.com>