Acceptance testing for the withdrawal path

[Inphi]

We won't be able to finalize withdrawals in a live devnet. But we should be able to prove withdrawals at least Perhaps withdrawal finalization can be done only on kurtosis as a separate step.

[ajsutton]

Kurtosis also can't time travel so it's not going to be useful here either. We could add time travel to the sys go backend easily though.