Our OpenStack UPI job regenerates install-config by running `openshift-install create install-config` while a `install-config.yaml` file already exists in the working directory. We do that to fill in unset properties with default values.

This has the effect of adding default values for apiVIP and ingressVIP of 10.0.0.5 and 10.0.0.7 respectively However, we set the machine subnet to a different value than 10.0.0.0/x.

See https://prow.ci.openshift.org/view/gs/origin-ci-test/logs/periodic-ci-shiftstack-shiftstack-ci-main-periodic-4.12-e2e-openstack-upi/1566076303977746432