if no containers, don't show service status of podman containers.

nixos/modules/nixos/system/motd/default.nix

@@ -53,8 +53,9 @@ let
         zpool list -Ho name,cap,size | awk '{ printf("%-10s%+3s used out of %+5s\n", $1, $2, $3); }' | sed -e 's/^/  /'
       fi
       printf "\n"
-      printf "$BOLDService status$ENDCOLOR\n"
       
+      if [[ -n "$service_status" ]]; then
+      printf "$BOLDService status$ENDCOLOR\n"
         while IFS= read -r line; do
           if [[ $line =~ ".scope" ]]; then
             continue
@@ -69,6 +70,7 @@ let
             echo "service status unknown"
           fi
         done <<< "$service_status"
+      fi
     '';
   cfg = config.mySystem.system.motd;
 in