Remove code duplication in delete methods

This patch removes code duplication in delete methods of service
compute client unit tests.

Change-Id: Ifc2eb17bbe4f2e658f657760510bdc08e3d60251
diff --git a/tempest/tests/services/compute/test_agents_client.py b/tempest/tests/services/compute/test_agents_client.py
index a8d4c87..9493a32 100644
--- a/tempest/tests/services/compute/test_agents_client.py
+++ b/tempest/tests/services/compute/test_agents_client.py
@@ -12,10 +12,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import httplib2
-
-from oslotest import mockpatch
-
 from tempest.services.compute.json import agents_client
 from tempest.tests import fake_auth_provider
 from tempest.tests.services.compute import base
@@ -71,11 +67,10 @@
             version="2", architecture="x86_64", os="linux")
 
     def _test_delete_agent(self):
-        mocked_resp = (httplib2.Response({'status': 200}), None)
-        self.useFixture(mockpatch.Patch(
+        self.check_service_client_function(
+            self.client.delete_agent,
             'tempest.common.service_client.ServiceClient.delete',
-            return_value=mocked_resp))
-        self.client.delete_agent("1")
+            {}, agent_id="1")
 
     def _test_update_agent(self, bytes_body=False):
         self.check_service_client_function(