Apply etcd_extra_vars to etcd-events.env as well. (#4219)
Apply etcd_extra_vars to etcd-events.env as well. (#4219)

This change ensures that etcd_extra_vars variable applies
to events etcd as well.
kubernetes-incubator/kargo,kubernetes-sigs/kubespray,kubernetes-incubator/kubespray,kubernetes-sigs/kubespray,Atoms/kubespray,kubernetes-incubator/kubespray,Atoms/kubespray,kubernetes-sigs/kubespray,kubernetes-sigs/kubespray,kubernetes-incubator/kargo,Atoms/kubespray,Atoms/kubespray