Add ssh_redirect_user

Author: yaseenhamdulay

cluster/gce/gci/master.yaml

@@ -4,6 +4,7 @@ users:
 - name: etcd
   homedir: /var/etcd
   lock_passwd: true
+  ssh_redirect_user: true
 
 write_files:
   - path: /etc/systemd/system/kube-master-installation.service