[FIX] purchase: Set bank account on bill

Fixes #44133
Before this commit, the Bank account on the new Bill created from the PO was not set due to missing methods to set those fields.

This commits adds missing methods to set Bank account.

closes odoo/odoo#44252

X-original-commit: f66042c9
Signed-off-by: Laurent Smet <smetl@users.noreply.github.com>

addons/purchase/models/account_invoice.py

@@ -67,6 +67,7 @@ class AccountMove(models.Model):
 
         self.purchase_id = False
         self._onchange_currency()
+        self.invoice_partner_bank_id = self.bank_partner_id.bank_ids and self.bank_partner_id.bank_ids[0]
 
     @api.model_create_multi
     def create(self, vals_list):