cli/command/container: ensure channel is allocated
cli/command/container: ensure channel is allocated

Signed-off-by: Stephen J Day <63efd86fa22882ae89b6027b22a36e4db1f4214d@docker.com>

thaJeztah/cli,ashfall/cli,thaJeztah/cli,docker/cli,dnephin/cli,redpanda/cli,redpanda/cli,docker/cli,cpuguy83/cli,cpuguy83/cli,ashfall/cli,allencloud/cli,dnephin/cli,allencloud/cli