update sahara.conf file for kolla

The use of [keystone_authtoken] credentials for trust creation is now
 deprecated. refer to [1][2][3]

[1] https://github.com/openstack/sahara/blob/d16f07ea3ce448033774b69c142453cc7fa79383/releasenotes/notes/trustee-conf-section-5994dcd48a9744d7.yaml
[2] https://docs.openstack.org/sahara/latest/configuration/descriptionconfig.html
[3] https://github.com/openstack/sahara/blob/d60a3b152b4ff3ba48cb9199eac1aad8e182f6e1/sahara/utils/openstack/keystone.py#L116

Change-Id: I75002c6221268a3371585cf270dee18186471ef5

ansible/roles/sahara/templates/sahara.conf.j2

@@ -15,12 +15,6 @@ connection = mysql+pymysql://{{ sahara_database_user }}:{{ sahara_database_passw
 
 [keystone_authtoken]
 auth_uri = {{ internal_protocol }}://{{ kolla_internal_fqdn }}:{{ keystone_public_port }}
-project_domain_name = {{ default_project_domain_name }}
-project_name = service
-user_domain_name = {{ default_user_domain_name }}
-username = {{ sahara_keystone_user }}
-password = {{ sahara_keystone_password }}
-auth_url = {{ admin_protocol }}://{{ kolla_internal_fqdn }}:{{ keystone_admin_port }}
 auth_type = password
 admin_user = {{ sahara_keystone_user }}
 admin_password = {{ sahara_keystone_password }}
@@ -57,3 +51,11 @@ policy_file = {{ sahara_policy_file }}
 
 [profiler]
 enabled = False
+
+[trustee]
+project_domain_name = {{ default_project_domain_name }}
+project_name = service
+user_domain_name = {{ default_user_domain_name }}
+username = {{ sahara_keystone_user }}
+password = {{ sahara_keystone_password }}
+auth_url = {{ admin_protocol }}://{{ kolla_internal_fqdn }}:{{ keystone_admin_port }}