Remove releated role_tree_dn test
Remove releated role_tree_dn test

The role_tree_dn option has been removed, so we can remove
releated test.

Change-Id: I2a344fe76dc70c68dc33793e61cc45d2b1420859

rajalokan/keystone,ilay09/keystone,ilay09/keystone,mahak/keystone,rajalokan/keystone,mahak/keystone,openstack/keystone,ilay09/keystone,openstack/keystone,openstack/keystone,rajalokan/keystone,mahak/keystone