Missing timeout propagation in Automaton::MinimizeMoore

[davisjam]

Similar to #3, but for Automaton::MinimizeMoore.

I am experimenting with the regex /this is a regex a{48} done/. The fa has about 700K states.

In this case it appears to be that the loop to build distinguishable can take quite a long time and result in OOM errors. Adding a CheckTimeout within that loop resolves the problem.