As it was announced [1] global bindep-fallback.txt was removed and now
projects need to have a local bindep.txt to be able to install binary
dependencies for testing.
We use lxml which requires a number of underlying packages.
[1] http://lists.openstack.org/pipermail/openstack-discuss/2019-June/007272.html
Change-Id: Ie635fa5d613cb89f8de8c8c8d5b119621acb926d
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>