I rolled back the install script to the 7.1.0 version, which works. But, the 7.1.2 version leaves spamassassin package in a broken state that’s not easy to undo. I recommend starting over with a fresh OS install.
If that’s not possible, it may be that using virtualmin-install.sh --uninstall will remove enough of the mess to allow it to install successfully, though I haven’t tested that. (This should only be used on a system that has nothing of value on it. It is very destructive. And, it may or may not do anything useful in this circumstance. Until now, we never had a case where the configure step of a package was mess up in this particular way. It’s real messy. I really recommend just starting over if you can.)