* Revert "If pip install requirements.txt fails, upgrade pip (#32399)"
This reverts commit 2fb4f547a9.
* Avoid pep8 user warning in 1.7.1.
* Limit cryptography version for Windows tests.
* Upgrade pip in virtualenv for pip test.
* Upgrade pip in virtualenv for groupby_filter test.
* Upgrade pip in virtualenv for template_jinja2_latest test.