[oslo][requirements][release] oslo.db lower-constraints job broken

Hi, Our stable/stein patches in oslo.db are currently failing the lower-constraints job due to [0]. I assume master has the same problem since there haven't been any changes since branching. It looks like the problem is that psycopg2 < 2.7 doesn't work with postgresql 10, and we're getting 10 now on bionic. The simple solution is to bump the lower-constraint, but I'm not sure how that's going to work for the stable branch since we can't change requirements there. How do we proceed? Thanks. -Ben 0: https://bugs.launchpad.net/oslo.db/+bug/1821400