metropolis/cli/metroctl: dont segfault on missing status

Change-Id: Ib1a594e0ccca0f6a993e651b62e8adcfb9dc1ea4
Reviewed-on: https://review.monogon.dev/c/monogon/+/1814
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/metropolis/cli/metroctl/table_node.go b/metropolis/cli/metroctl/table_node.go
index 6e74682..c708443 100644
--- a/metropolis/cli/metroctl/table_node.go
+++ b/metropolis/cli/metroctl/table_node.go
@@ -17,7 +17,11 @@
 	state := n.State.String()
 	state = strings.ReplaceAll(state, "NODE_STATE_", "")
 	res.add("state", state)
-	res.add("address", n.Status.ExternalAddress)
+	address := "unknown"
+	if n.Status != nil && n.Status.ExternalAddress != "" {
+		address = n.Status.ExternalAddress
+	}
+	res.add("address", address)
 	res.add("health", n.Health.String())
 
 	var roles []string