positioner: Load position config after deferred moves
When deferred moves are done for all the items, we should load the configuration afterwards to make sure any items on the configuration are placed in the correct place.
Deferred moves often happen during folder view margin resizing or after folderitems loading/changing. Thus they can sometimes load unexpected positions (because they are looking for the best possible position for the item), even if the user has configured them to load in some specific way.