Use 'none' auth plugin
Use 'none' auth plugin

since keystoneauth 3.0.0 there is a proper 'none' auth plugin to
use for standalone services deployed w/o Keystone support.

Use this plugin instead of 'admin_token' for auth_type specified as
variants of 'None'.

Change-Id: I425f03574858dd582118d5544381af703134da72

openstack/os-client-config