test: reduce log noise

The previous code intended to silence the most relevant source of log noise
("connexion.operations"), but due to the missing trailing "s", it failed
to do so.
Now all debug messages emitted during a test are silenced.

src/rest/test/__init__.py

@@ -9,7 +9,9 @@ from src.rest.encoder import JSONEncoder
 class BaseTestCase(TestCase):
 
     def create_app(self):
-        logging.getLogger('connexion.operation').setLevel('ERROR')
+        # silence the noise debug log of the relevant modules
+        for log_name in ("connexion", "openapi_spec_validator"):
+            logging.getLogger(log_name).setLevel('ERROR')
         app = connexion.App(__name__, specification_dir='../swagger/')
         app.app.json_encoder = JSONEncoder
         app.add_api('swagger.yaml')