[FIX] point_of_sale: digits field doesn't exist on currency

As the field digit doesn't exist on currency, we use decimal_places
instead which is the field containing the number of digits of the
corresponding rounding field

addons/point_of_sale/models/pos_order.py

@@ -981,7 +981,7 @@ class ReportSaleDetails(models.AbstractModel):
             payments = []
 
         return {
-            'currency_precision': user_currency.digits,
+            'currency_precision': user_currency.decimal_places,
             'total_paid': user_currency.round(total),
             'payments': payments,
             'company_name': self.env.user.company_id.name,