Bot freezes when playing Root Cellar

[elucidarian]

game #167237401 with two bots

Rattington on turn 15 played two Mills and then stopped after playing a Root Cellar. Seems like another instance when the bots don't know how to handle gaining debt.

It might be notable that I gave the bot did not buy the Root Cellar. I selected it when trashing a Silver with a Swindler.