[Checkins] [zopefoundation/Zope] e626cf: Fix deprecation warning.

[Michael Howitz]

  Branch: refs/heads/py38
  Home:   https://github.com/zopefoundation/Zope
  Commit: e626cf8a0de8e18a87fef0a8a522b8d9136f1180
      https://github.com/zopefoundation/Zope/commit/e626cf8a0de8e18a87fef0a8a522b8d9136f1180
  Author: Michael Howitz <mh at gocept.com>
  Date:   2019-02-08 (Fri, 08 Feb 2019)

  Changed paths:
    M src/OFS/tests/testObjectManager.py

  Log Message:
  -----------
  Fix deprecation warning.