This is no longer valid with the switch to ephemeral heat for
deployments.
We dropped the tripleoclient code for minion in [1]. With this patch
dropping UndercloudMinion environments.
[1] https://review.opendev.org/c/openstack/python-tripleoclient/+/811995
Change-Id: I097b9b69ba6ed132b7c9fb0bc0e42f06808c6ab2