Move keystone::auth into service_config_settings

Move keystone::auth into service_config_settings

This patch moves the keystone::auth settings for all
services into the new service_config_settings section. This
is important because we execute the keystone commands via
puppet only on the role containing the keystone service
and without these settings it will fail.

Note that yaql merging/filtering is used here to ensure that
service_config_settings is optional in service templates,
and also that we'll only deploy hieradata for a given
service on a node running the service (the key in
the service_config_settings map must match the service_name
in the service template for this to work).

e.g the following will result in only deploying keystone: 123
in hiera on the role running the "keystone" service,
regardless of which service template defines it.

  service_config_settings:
    keystone:
      keystone: 123

Co-Authored-By: Steven Hardy <shardy@redhat.com>
Change-Id: I0c2fce037a1a38772f998d582a816b4b703f8265
Closes-bug: 1620829