Conversions between lazy and strict StateT

Should there be functions to convert between strict and lazy `StateT` variants?

```haskell
strictToLazyStateT :: Strict.StateT s m a -> Lazy.StateT s m a
strictToLazyStateT (Strict.StateT f) = Lazy.StateT f

lazyToStrictStateT :: Lazy.StateT s m a -> Strict.StateT s m a
lazyToStrictStateT (Lazy.StateT f) = Strict.StateT f
```