[Checkins] [zopefoundation/Zope] c247a8: Update to a new persistent version.

[Michael Howitz]

  Branch: refs/heads/update-persistent
  Home:   https://github.com/zopefoundation/Zope
  Commit: c247a84ac753b037160066530aeaa43384ed3d42
      https://github.com/zopefoundation/Zope/commit/c247a84ac753b037160066530aeaa43384ed3d42
  Author: Michael Howitz <mh at gocept.com>
  Date:   2020-03-06 (Fri, 06 Mar 2020)

  Changed paths:
    M constraints.txt
    M requirements-full.txt
    M versions-prod.cfg

  Log Message:
  -----------
  Update to a new persistent version.

After beeing merged it allows to run the tests of AccessControl etc. against
that version.