use 'k8s.gcr.io' instead of 'gcr.io/google-containers'
use 'k8s.gcr.io' instead of 'gcr.io/google-containers'

Signed-off-by: SataQiu <97f8eee8b07d4f77a6c69aae5541a91d543b9018@qq.com>

kubernetes/kubeadm,kubernetes/kubeadm