Add format to docker stack ls
Add format to docker stack ls

Signed-off-by: Boaz Shuster <dcfbdecb7964372c22343bdfc0ea59b1d969bfd5@gmail.com>

riyazdf/cli,redpanda/cli,e11137/cli,ashfall/cli,redpanda/cli,docker/cli,cpuguy83/cli,docker/cli,riyazdf/cli,dnephin/cli,e11137/cli,cpuguy83/cli,thaJeztah/cli,allencloud/cli,Zebrilee/cli,Zebrilee/cli,ashfall/cli,thaJeztah/cli,allencloud/cli,dnephin/cli