[contracts] Update `setState` method to work on non-settled apps vs just "ON" state apps

[snario]

There is a bug in the setState function which checks that the app is ON. See

https://github.com/counterfactual/monorepo/blob/99fc5556d212843dd1c0c4f6c90b4043256e4607/packages/contracts/contracts/mixins/MixinSetState.sol#L45

It should instead check if the app is either ON or DISPUTE (but not yet timed out).