A particular case of sub-traversability with the state monad.
This is not a full traverse because the final state is not returned.
This allows us to implement this interface for (potentially) infinite data types.
This interface has a law connecting to the `Functor` superinterface:
`traverseSt () $ const $ pure . f` must act as `map f`.
Parameters: f
Constraints: Functor f
Methods:
traverseSt : s -> (s -> a -> (s, b)) -> f a -> f b
Implementations:
TraversableSt Stream TraversableSt Colist TraversableSt LazyList Traversable f => TraversableSt f