Remove unnecessary wrapping of tests
Remove unnecessary wrapping of tests

The cited issue https://bugs.python.org/issue3210 is fixed in all the
versions of Python that we test against.

pfmoore/pip,xavfernandez/pip,xavfernandez/pip,pradyunsg/pip,xavfernandez/pip,pypa/pip,sbidoul/pip,pypa/pip,pfmoore/pip,sbidoul/pip,pradyunsg/pip