[Checkins] [zopefoundation/zope.sendmail] cff9a7: Use Python 3.8 final on Travis CI

[Marius Gedminas]

  Branch: refs/heads/master
  Home:   https://github.com/zopefoundation/zope.sendmail
  Commit: cff9a7d83818a1a79b2a21a2f3c1d57d11e3e358
      https://github.com/zopefoundation/zope.sendmail/commit/cff9a7d83818a1a79b2a21a2f3c1d57d11e3e358
  Author: Marius Gedminas <marius at gedmin.as>
  Date:   2019-10-23 (Wed, 23 Oct 2019)

  Changed paths:
    M .travis.yml

  Log Message:
  -----------
  Use Python 3.8 final on Travis CI