[FIX] stock: serial number

- Activate the option "Track Lots or Serial Numbers".
- Set the outgoing process as 3-step one.
- Create a stockable product for which the tracking is "By Unique Serial
  Number".
- Go to Sales > Sales > Sales Orders.
- Create a Quotation for the created product and confirm it. A picking
  is generated but it is waiting availability.
- You are sure to have this product in stock so you force the
  availability and assign the serial number (001) you want to transfer
  in the operation lot details.
- Validate the picking. By doing this, it creates a negative quant in
  the origin location (WH/Stock) and it creates a positive quant in the
  destination location (WH/Packing Zone). The two quants are linked to
  each other.
- Go to Inventory > Inventory Control > Inventory Adjustments.
- Create an inventory in WH/Stock  for all products and set it in
  progress.
- You want to correct the negative quantity you have so set the real
  quantity of product B to 0.
- Validate the inventory and you get the following warning: "The serial
  number 001 is already in stock.Otherwise make sure the right
  stock/owner is set".

We should allow a quantity larger than 1.0 temporary, so it allows the
system to reconcile the quants.

opw-685825