Updated openstack/openstack
Project: openstack/heat  8be4e9041c5b9c5936656ae037c6d696a90f0f53

Handle clients that don't accept auth_url=None

Some clients fail when passed None as the auth_url. Pass them an empty
string instead when the auth_url is None.

Change-Id: Ie7cf788a00660efae578b6444ee231876025ebba
Closes-Bug: #1332991
Closes-Bug: #1334492