This is required for some tempest tests and in turn to achieve 100%
refstack certification for clouds deployed by Kolla. tempurl is default in
Swift[0] but we're missing as we override the pipeline.

[0] https://github.com/openstack/swift/blob/\
    b86bf15a644db4438770801a312fe074a09c91ef/\
    etc/proxy-server.conf-sample#L97

Change-Id: I0e36fcd7a785f878005d51159eb51725c284229c