tasks: Install distribution packages before pip_install
tasks: Install distribution packages before pip_install

The distribution packages should be installed first in order to prevent
the pip_install role to mess with the systemd pip/virtualenv packages
if they already match our requirements.

Closes-Bug: #1773333
Change-Id: I7290a362ebec010a2b346cecfff42fef55b3ce6a

openstack/openstack-ansible-openstack_hosts,openstack/openstack-ansible-openstack_hosts