The changes which seem to fix the issue (during testing we haven't hit it again) are present in openstack-tempest-18.0.0-5.el7ost package which is available in the latest puddles.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://access.redhat.com/errata/RHBA-2019:0088