[FIX] account: analytic cost

- Set a cost of 12.34 for product P
- Create manually a new analytic entry
- Choose product P
- Set desired quantity

The analytic amount is set to 12.00.

This is because `move_id` is empty, therefore `currency_id` is empty as
well and `decimal_places` is zero

opw-1924184

closes odoo/odoo#30869

addons/account/models/account_analytic_line.py

@@ -44,7 +44,7 @@ class AccountAnalyticLine(models.Model):
         # Compute based on pricetype
         amount_unit = self.product_id.price_compute('standard_price', uom=unit)[self.product_id.id]
         amount = amount_unit * self.unit_amount or 0.0
-        result = round(amount, self.currency_id.decimal_places) * -1
+        result = round(amount, self.currency_id.decimal_places if self.currency_id else 2) * -1
         self.amount = result
         self.general_account_id = account
         self.product_uom_id = unit