cloudron-setup: do not cat to stdout

scripts/cloudron-setup

@@ -42,7 +42,7 @@ if [[ "${disk_size_gb}" -lt "${MINIMUM_DISK_SIZE_GB}" ]]; then
 fi
 
 # do not use is-active in case box service is down and user attempts to re-install
-if systemctl cat box.service 2>/dev/null; then
+if systemctl cat box.service >/dev/null 2>&1; then
     echo "Error: Cloudron is already installed. To reinstall, start afresh"
     exit 1
 fi