This reverts commit 0aa4981305.
The repo_server and repo_build shouldn't assume to be configured
by openstack_hosts role yet, because their environment is incomplete.
On top of that, when artifacting will be introduced, these roles could
be running outside the openstack hosts (for example, on deploy nodes).
Change-Id: I47a58a46a695b504646bca8100758decb07cbb98