Fix adding QoS policy  to the cleanup

The _create_qos_policy method mistakenly added the policy object
to the cleanup, whereas delete_qos_policy expects a policy_id

Fixes-Bug: PRODX-52288

Change-Id: If35d7e5dd14a508085dde4e719f6f1e4386d8e66
diff --git a/neutron_tempest_plugin/scenario/test_qos.py b/neutron_tempest_plugin/scenario/test_qos.py
index 74be216..b0921c8 100644
--- a/neutron_tempest_plugin/scenario/test_qos.py
+++ b/neutron_tempest_plugin/scenario/test_qos.py
@@ -140,7 +140,8 @@
                                         shared=True)
         self.qos_policies.append(policy['policy'])
         self.addCleanup(test_utils.call_and_ignore_notfound_exc,
-            self.os_admin.network_client.delete_qos_policy, policy)
+                        self.os_admin.network_client.delete_qos_policy,
+                        policy['policy']['id'])
         return policy['policy']['id']
 
     def _create_qos_bw_limit_rule(self, policy_id, rule_data):