Update default etcd server to 3.2.24 for kubernetes 1.12
Update default etcd server to 3.2.24 for kubernetes 1.12

Signed-off-by: Timothy St. Clair <timothysc@gmail.com>

Kubernetes-commit: ad2ed0e7dfe1ac914e6d1ecd369d57111fd365c6

kubernetes/apiextensions-apiserver,kubernetes/apiextensions-apiserver