add function to add a Python package during configure time
Problem
See quality/dune-testtools!142 (closed):
the module dune-testtool
contains a Python package that needs to be installed during configure time so that tests within the module are run correctly.
Solution
A possible solution is to add a cmake function that allows installation of a Python package during configure time (after the internal venv is setup).
Alternative: add a flag to the existing install_python
function to move installation of the package from the end of the build to the configure phase.