let addCleanup use the current client

Change-Id: I3c225897ff3f68c1f9fc7b8f82e897bac75d6e5c
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index 2da2f92..7665c6a 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -707,7 +707,7 @@
 
         self.assertEqual(network['name'], name)
         self.addCleanup(test_utils.call_and_ignore_notfound_exc,
-                        self.networks_client.delete_network,
+                        networks_client.delete_network,
                         network['id'])
         return network
 
@@ -860,7 +860,7 @@
         )
         floating_ip = result['floatingip']
         self.addCleanup(test_utils.call_and_ignore_notfound_exc,
-                        self.floating_ips_client.delete_floatingip,
+                        client.delete_floatingip,
                         floating_ip['id'])
         return floating_ip