Change keypair client to return one value and update tests

Partially implements: blueprint clients-return-one-value

Change-Id: Ief3c882164917062f1874182ba9ab1732f347d0d
diff --git a/tempest/api/compute/test_authorization.py b/tempest/api/compute/test_authorization.py
index 60cb812..dfb3c43 100644
--- a/tempest/api/compute/test_authorization.py
+++ b/tempest/api/compute/test_authorization.py
@@ -68,8 +68,7 @@
         cls.image = cls.images_client.get_image(image_id)
 
         cls.keypairname = data_utils.rand_name('keypair')
-        resp, keypair = \
-            cls.keypairs_client.create_keypair(cls.keypairname)
+        cls.keypairs_client.create_keypair(cls.keypairname)
 
         name = data_utils.rand_name('security')
         description = data_utils.rand_name('description')
@@ -202,7 +201,7 @@
         finally:
             # Next request the base_url is back to normal
             if (resp['status'] is not None):
-                resp, _ = self.alt_keypairs_client.delete_keypair(k_name)
+                self.alt_keypairs_client.delete_keypair(k_name)
                 LOG.error("Create keypair request should not happen "
                           "if the tenant id does not match the current user")