[Checkins] [zopefoundation/Zope] 305f70: Fix pip on Travis (#785)

[Michael Howitz]

  Branch: refs/heads/py39
  Home:   https://github.com/zopefoundation/Zope
  Commit: 305f70bed6ed7b9a41d831658b46cfbac4346d3f
      https://github.com/zopefoundation/Zope/commit/305f70bed6ed7b9a41d831658b46cfbac4346d3f
  Author: Michael Howitz <mh at gocept.com>
  Date:   2020-02-11 (Tue, 11 Feb 2020)

  Changed paths:
    M .travis.yml

  Log Message:
  -----------
  Fix pip on Travis (#785)

Without these changes even pip --version fails because it cannot import pip. 😞