This role is intended to ensure that the `pip:` module, and jobs that
may wish to use `pip` from the shell, have the necessary requirements.
It is intended as a partial replacement for the pip-and-virtualenv
element in diskimage-builder, which currently pre-installs pip on our
infra CI images during image build.
We wish to remain broady compatible with this element, but not
replicate some of the more problematic areas of its implementation.
By default, this installs the system packages for pip and setuptools
(the latter being a requirement of the Ansible pip module, which
imports it directly, despite pip itself not requiring it).
In this role, we ensure the libraries for the currently running
ansible_python_interpreter version are installed.
There is provision to provide a flag to install the packages directly
from upstream via get-pip.py, although this is not recommended.
Story: #2007386
Task: #39309
Change-Id: Iac2d518a66caf1b801273225f75a0a748412903c
5068744eff