As with the previous similar changes, this is intended to catch
problems as they happen instead of ignoring them and continuing on
to potentially fail later. Setting this on all existing scripts
will allow us to enforce use via Jenkins.
Change-Id: Iad2d490c86dceab148ea9ab08f457c49a5d5352e
The element bind mounts a pip cache inside the image build chroot so
that pip downloads can be reused across image builds. While similar
in purpose to the PyPi element that sets up a mirror, this element
just allows for a reusable download cache and doesn't require anything
to be setup beforehand.
The pip-cache element is not concurrency safe, and that is indicated
in the README for the element. An upstream bug was file as well:
https://github.com/pypa/pip/issues/1141
Change-Id: Ibd1d4ea17c24923ed939357ada95b781e3179cfd
