Fixed failing test

Author: david-yz-liu

server/autotest_server/tests/fixtures/specs/py/simple.json

@@ -14,7 +14,7 @@
             ],
             "timeout": 30,
             "tester": "unittest",
-            "output_verbosity": 2,
+            "output_verbosity": "2",
             "extra_info": {
                 "criterion": "criterion",
                 "display_output": "instructors",