[Checkins] [zopefoundation/zope.authentication] a8d2cd: Fix supported Python versions.

[Michael Howitz]

  Branch: refs/heads/config-with-pure-python
  Home:   https://github.com/zopefoundation/zope.authentication
  Commit: a8d2cdfd93ed006a77de65de9b9e593974fa12be
      https://github.com/zopefoundation/zope.authentication/commit/a8d2cdfd93ed006a77de65de9b9e593974fa12be
  Author: Michael Howitz <mh at gocept.com>
  Date:   2020-05-14 (Thu, 14 May 2020)

  Changed paths:
    M CHANGES.rst
    M setup.py

  Log Message:
  -----------
  Fix supported Python versions.