CX: Stop filling RS slides if the game is close to the end and no started product needs it

[Sagre]

Currently every workpiece that is not needed anymore is put into a RS slide. This makes a lot of sense in the beginning of the game, since the more complex orders that will pop up in the run of the game will benefit from already stored workpieces. However, at the end of the game it is unlikely that we will start with new order. Thus taking the time to drive to a RS and putting the workpiece into the slide, which takes around 1-2 min, could be used to finish and deliver an additional product. Thus, we should rather discard a workpiece at the end of a game instead of wasting the time

[morxa]

This should be obsolete once we have promises and requests, see fawkesrobotics/fawkes#17 (comment).