Fixed Basic optim tempest test

In this changeset, I made some fixes in order to make the
multinode test pass on the gate.

Change-Id: I2433748a78c87b15893ea69964561955b478eebd

watcher_tempest_plugin/tests/api/admin/test_audit.py

@@ -58,6 +58,7 @@ class TestCreateUpdateDeleteAudit(base.BaseInfraOptimTest):
         audit_params = dict(
             audit_template_uuid=audit_template['uuid'],
             audit_type='CONTINUOUS',
+            interval=7200,
         )
 
         _, body = self.create_audit(**audit_params)