Make minikube the default ephemeral cluster

This PR makes minikube the default ephemeral cluster irrespective of container runtime or image OS. The idea is to run Ubuntu tests only for the time being in different repos until CI is stable. Centos e2es are failing more often. Making minikube ephemeral cluster makes sure that we test ironic as a k8s deployment instead of local containers.

Signed-off-by: Kashif Khan <kashif.khan@est.tech>

lib/common.sh

@@ -330,11 +330,7 @@ export KUBERNETES_BINARIES_VERSION="${KUBERNETES_BINARIES_VERSION:-${KUBERNETES_
 export KUBERNETES_BINARIES_CONFIG_VERSION=${KUBERNETES_BINARIES_CONFIG_VERSION:-"v0.15.1"}
 
 # Ephemeral Cluster
-if [[ "${CONTAINER_RUNTIME}" = "docker" ]]; then
-  export EPHEMERAL_CLUSTER=${EPHEMERAL_CLUSTER:-"kind"}
-else
-  export EPHEMERAL_CLUSTER="minikube"
-fi
+export EPHEMERAL_CLUSTER="minikube"
 
 # Kubectl version (do not forget to update KUBECTL_SHA256 when changing KUBERNETES_VERSION!)
 export KUBECTL_VERSION="${KUBECTL_VERSION:-${KUBERNETES_BINARIES_VERSION}}"