report the correct return code

Signed-off-by: Mattia Rizzolo <mapreri@ubuntu.com>

cron.sh

@@ -33,7 +33,7 @@ run_script() (
     "$script" > "$output" 2>&1 || ret=$?
     if [[ "${ret-0}" -ne 0 ]]; then
         echo "Deploy script $(basename "${script}") failed!"
-        echo "Return code: $?"
+        echo "Return code: $ret"
         echo "Script output"
         echo "============="
         cat "${output}"