Make the internal queue monadic

`Data.Graph.Inductive.Internal.Queue` isn't efficient for persistent use. It would be easier to ensure that it's not accidentally used persistently if it's given a monadic interface. It should probably also be benchmarked against other queue implementations, such as `Control.Monad.Queue.Corec` from [`control-monad-queue`](https://hackage.haskell.org/package/control-monad-queue), [my own considerable simplification thereof](https://gist.github.com/treeowl/5c14a43869cf14a823473ec075788a74), or perhaps something fancier in `ST`.