With the current swift-proxy healthcheck the container status is
unhealty even the service is up.
The used ps/grep won't return the swift proxy processes as the
output gets truncated:
()[root@overcloud-controller-0 /]$ ps -e
PID TTY TIME CMD
1 ? 00:00:00 dumb-init
6 ? 00:02:52 swift-proxy-ser
28 ? 00:00:25 swift-proxy-ser
4753 pts/1 00:00:00 sh
4797 pts/1 00:00:00 ps
As a result we end up in the else, checking the cache.
This moves the if to use pgrep instead.