Fix tempest test revet_client typo

TrivialFix

Change-Id: Ib4a0c50f699edb1cc2ea669ac711eb2f537be417
diff --git a/cinder/tests/tempest/cinder_clients.py b/cinder/tests/tempest/cinder_clients.py
index aad32d4..8d9abe7 100644
--- a/cinder/tests/tempest/cinder_clients.py
+++ b/cinder/tests/tempest/cinder_clients.py
@@ -36,5 +36,5 @@
         self.consistencygroups_adm_client = (
             consistencygroups_client.ConsistencyGroupsClient(auth_provider,
                                                              **params))
-        self.volume_revet_client = (
+        self.volume_revert_client = (
             volume_revert_client.VolumeRevertClient(auth_provider, **params))