Pip added as a test requirement to most things

It seems that many things get a pip requirement added to the tests. This seems unnecessary since most things include pip in the installing environment as it is a host dependency of most python packages. As an example https://github.com/regro/cf-graph-countyfair/blob/master/audits/grayskull/attrs_19.3.0.yml

Start with audits/grayskull/attrs_19.3.0.yml and inspect how test requirements are generated or added across recipes. Determine which pip requirements are redundant, then verify that generated recipes no longer include unnecessary pip test requirements while retaining any genuinely required dependencies.

Written by the indexing model from the issue text.