Changes in python packaging tooling mean that the wsgi_scripts
functionality via PBR may not longer function.
This patch switches blazar from using the PBR wsgi_scripts method to
using a new wsgi module that provides the same behavior as the generated
wsgi scripts provided.
A related devstack patch enables devstack to setup uWSGI to use the new
module path instead of the generated wsgi scripts.
For more details see the proposed OpenStack goal [1].
[1] https://review.opendev.org/c/openstack/governance/+/902807
Change-Id: Ib16d5d1ea5d7416d7b1f026f771d6c2b77657970
3ccbf2ea5c