Subscribe to a gnmic network device state updates. More information: https://gnmic.kmrd.dev/cmd/subscribe.
gnmic --address ip:port subscribe --path path
gnmic -a ip:port subscribe --path path --sample-interval 30s
gnmic -a ip:port subscribe --path path --stream-mode on-change --heartbeat-interval 1m
gnmic -a ip:port subscribe --path path --mode once
gnmic -a ip:port subscribe --path path --encoding json_ietf