[1.20] Turtle casting environment implements method incorrectly

[miyucomics]

The stackOk predicate is not used in this method, which means it will never return null if it has any items, even if the item returned does not match the predicate. This causes a problem with conjured compasses in Hexical due to an OpRead mixin looking for conjured compasses specifically. This may also break with lamps that look for lamps specifically.