https://github.com/jimweirich/builder/pull/15 should fix the issue (and another unrelated one fwiw).
-- Diego Elio Pettenò <flamee...@flameeyes.eu> -- To UNSUBSCRIBE, email to debian-bugs-rc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
