[FIX] stock_mts_mto_rule: multiple procs same product

[ferran-S73]

Reopen of https://github.com/OCA/stock-logistics-warehouse/pull/1872

When launching 2 mts+mto procurements for the same product, if the first one has a greater o equal qty than the second, the second won't run it's mto action. This is because the replenishment move gets confirmed whereas the original moves are still in drat state.

Steps to reproduce the issue:

• Configure a product with the mts+mto rule and some other rule (in my case it was a manufacturing rule)
• Launch it's rule twice at the same time (i.e. confirming a sales order with two lines of the same product) without having any stock for the product. First line with 10units, second with 5.
• Only the procurement for the first line will apply it's mto rule (in my case it only creates one manufacturing order with 10 units).

Debugging the code I found out that when the _run_split_procurement method calls get_mto_qty_to_order for the second procurement the product virtual_available includes the qty that from the manufacturing order created by the first proc (it's move is confirmed) but isn't taking into account the sale's move as it is still in draft. So I think we can take this into account by keeping track of what's being replenished for each product.

[jbaudoux]

FYI @TDu @mt-software-de

[rousseldenis]

@ferran-S73