Distros that use rpm-ostree to provide atomic OS updates need special handling (running the test harness in a container, avoiding certain kickstart features, etc) Amit has posted an initial patch using a "has_rpmostree" feature flag: http://gerrit.beaker-project.org/#/c/3362/
http://gerrit.beaker-project.org/#/c/3362/
Amit has back-ported this to release-0.18 for the 0.18.3 release.
Beaker 0.18.3 has been released.