[TrivialFix] Remove unused statement in scenario/manager.py

Remove unused statment in scnario/manager.py to make code clean.

Change-Id: I9b90c0e55b5156407ab6ed6fd1bdce0d7ddd505d
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index 06b4b59..06aa531 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -1174,7 +1174,7 @@
         LOG.debug("Creating an encryption type for volume type: %s", type_id)
         client.create_encryption_type(
             type_id, provider=provider, key_size=key_size, cipher=cipher,
-            control_location=control_location)['encryption']
+            control_location=control_location)
 
     def create_encrypted_volume(self, encryption_provider, volume_type,
                                 key_size=256, cipher='aes-xts-plain64',