Don't cache downloaded wheels in our wheels mirror
Don't cache downloaded wheels in our wheels mirror

In the build-wheels role, parse stdout from all the build logs to
build up a unique list of all wheels downloaded from PyPI and delete
them from the wheelhouse, since this is only meant to provide built
wheels which are absent from PyPI. Those will be retrieved from our
caching proxy of PyPI served from the same mirror hosts anyway.

Change-Id: Id021ba5fd55bf6d43e99f9f3a7121aee8b0d0a6f

openstack-infra/project-config,openstack-infra/project-config