[FIX] sale_crm: if no company on lead use user currency

When displaying the `sale_amount_total` of an opportunity, the amount of
the related order are summed up in the opportunity company's currency.

But when creating a lead, we can leave the company empty which warranted
this commit adding in that instance a fall back on the current user
company currency.

closes #11611
opw-673167

addons/sale_crm/crm_lead.py

@@ -12,11 +12,12 @@ class crm_lead(models.Model):
     def _get_sale_amount_total(self):
         total = 0.0
         nbr = 0
+        company_currency = self.company_currency or self.env.user.company_id.currency_id
         for order in self.order_ids:
             if order.state in ('draft', 'sent'):
                 nbr += 1
             if order.state not in ('draft', 'sent', 'cancel'):
-                total += order.currency_id.compute(order.amount_untaxed, self.company_currency)
+                total += order.currency_id.compute(order.amount_untaxed, company_currency)
         self.sale_amount_total = total
         self.sale_number = nbr