[FIX] procurement_jit, stock: unreservation

We fix two problems with the 'unreserve' function on picking and sale order,
When a sale order is edited, we perform 'do_unreserve' on picking, it is not necessary and make us loose the done quantity put on the picking so we remove it.
When we unreserve a picking having a package level added through a put in pack or automatically added on reservation, the package level is set back to draft instead of being removed

--
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closes odoo/odoo#28188

addons/procurement_jit/sale.py

@@ -14,6 +14,5 @@ class SaleOrderLine(models.Model):
         for order in orders:
             reassign = order.picking_ids.filtered(lambda x: x.state=='confirmed' or (x.state in ['waiting', 'assigned'] and not x.printed))
             if reassign:
-                reassign.do_unreserve()
                 reassign.action_assign()
         return res

addons/stock/models/stock_picking.py

@@ -682,6 +682,7 @@ class Picking(models.Model):
     def do_unreserve(self):
         for picking in self:
             picking.move_lines._do_unreserve()
+            picking.package_level_ids.filtered(lambda p: not p.move_ids).unlink()
 
     @api.multi
     def button_validate(self):