Nut upsdev - Sep 2020 - Mailman config needs updated to unbreak DKIM verification

Hello mail admin,

Currently the nut-upsdev mailing list mail is mostly getting marked as SPAM (or
SPOOF) due to failed DKIM.

DKIM is trying to verify mail headers signed by the original sender, but using
the mailing list DKIM key (or lack thereof).

This occurs because the DKIM mail authentication looks for a authentication key
for the headers based on the HELO/ELHO user, but the message is DKIM signed by
the original user not the HELO/HELO user (which is nut-upsdev at
alioth-lists.debian.net) so the DKIM authentication of the headers fails.

Modern Mailman installations have an option to 'wrap' DKIM signed
headers so that DKIM is not misapplied to the mailing list's mail.

If you could enable that option it would be really helpful to avoid nut-upsdev
mail ending up on the spam folders of most recipients.

Regards,

Daniel