Log Message:
mailman: update to 2.1.34.

Update based on wip/mailman by Jesus Cea.
Clean some pkglint while here.

2.1.34 (26-Jun-2020)

  i18n

    - The Spanish translation has been updated by Omar Walid Llorente.

  Bug Fixes and other patches

    - The fix for LP: #1859104 can result in ValueError being thrown on
      attempts to subscribe to a list. This is fixed and extended to apply
      REFUSE_SECOND_PENDING to unsubscription as well.  (LP: #1878458)

    - DMARC mitigation no longer misses if the domain name returned by DNS
      contains upper case.  (LP: #1881035)

    - A new WARN_MEMBER_OF_SUBSCRIBE setting can be set to No to prevent
      mailbombing of a member of a list with private rosters by repeated
      subscribe attempts.  (LP: #1883017)

    - Very long filenames for scrubbed attachments are now truncated.
      (LP: #1884456)