The congress project is no longer maintained. This has been
retired since Victoria[1] and has not been used by other OpenStack
services since.
[1]: http://lists.openstack.org/pipermail/openstack-discuss/2020-April/014292.html
Depends-On: I21c9ab9820f78cf76adf11c5f0591c60f76372a8
Change-Id: I561ead226f714d98c8e06e6027715a64c3a8e47e