Remove unnecessary response check in InstanceUsageAuditLogTestJSON

The response checks in InstanceUsageAuditLogTestJSON are already
covered by schema check, so no need to check it in testcases.

Change-Id: Ia4415d5cd8c3ebc85a5aa72e78e884c6f6f7b48e
diff --git a/tempest/api/compute/admin/test_instance_usage_audit_log.py b/tempest/api/compute/admin/test_instance_usage_audit_log.py
index e4a2ffd..1b62249 100644
--- a/tempest/api/compute/admin/test_instance_usage_audit_log.py
+++ b/tempest/api/compute/admin/test_instance_usage_audit_log.py
@@ -31,27 +31,11 @@
     @decorators.idempotent_id('25319919-33d9-424f-9f99-2c203ee48b9d')
     def test_list_instance_usage_audit_logs(self):
         # list instance usage audit logs
-        body = (self.adm_client.list_instance_usage_audit_logs()
-                ["instance_usage_audit_logs"])
-        expected_items = ['total_errors', 'total_instances', 'log',
-                          'num_hosts_running', 'num_hosts_done',
-                          'num_hosts', 'hosts_not_run', 'overall_status',
-                          'period_ending', 'period_beginning',
-                          'num_hosts_not_run']
-        for item in expected_items:
-            self.assertIn(item, body)
+        self.adm_client.list_instance_usage_audit_logs()
 
     @decorators.idempotent_id('6e40459d-7c5f-400b-9e83-449fbc8e7feb')
     def test_get_instance_usage_audit_log(self):
         # Get instance usage audit log before specified time
         now = datetime.datetime.now()
-        body = (self.adm_client.show_instance_usage_audit_log(
+        self.adm_client.show_instance_usage_audit_log(
             urllib.quote(now.strftime("%Y-%m-%d %H:%M:%S")))
-            ["instance_usage_audit_log"])
-
-        expected_items = ['total_errors', 'total_instances', 'log',
-                          'num_hosts_running', 'num_hosts_done', 'num_hosts',
-                          'hosts_not_run', 'overall_status', 'period_ending',
-                          'period_beginning', 'num_hosts_not_run']
-        for item in expected_items:
-            self.assertIn(item, body)