Executing StockMove assign_try concurrently quantity assigned is greater than available quantity
Using postgresql, trytond 3.4
How to repeat it:
1. Create two productions with many input moves (so that assignment doesn't happen immediately)
2. Purchase enough quantity to fulfill one production
3. Assign productions concurrently (one after another)
Result: Both productions assigned
Expected Result: One production failed to assign
Expected result happens when assigning productions one by one, but not concurrently.