I've cast my usual eye over the regtest comparison for 13.40 - the only
significant change appears to be with figured-bass-continuation-forbid.log
where we've lost the error message. This would appear to be expected, as a
result of the fix to the figured bass code resulting from Reinhold's report
of the error. _However_. Shouldn't the regtest comparison for
figured-bass-continuation-forbid.ly flag the change as well?