Currently, kolla_keepalived_running may be created and deleted in
parallel which causes prechecks failure. The solution is using
run_once = true.
Closes-Bug: #1714407
Change-Id: I2ec8fc2e867c87175157af8acc11f57313bfaabe
Signed-off-by: Zhijiang Hu <hu.zhijiang@zte.com.cn>