Pass CI with python3.8
Recently some patches were applied to support python 3.8, but no CI was added for python 3.8.
This merge request adds that CI, and also fixes the pip source plugin to pass it's tests on python 3.8.
Recently some patches were applied to support python 3.8, but no CI was added for python 3.8.
This merge request adds that CI, and also fixes the pip source plugin to pass it's tests on python 3.8.