fix test

Author: jamesbaskerville

tests/integration/test_prompts.py

@@ -1,3 +1,5 @@
+import json
+
 from humanloop.client import Humanloop
 
 from tests.integration.conftest import TestIdentifiers
@@ -37,6 +39,7 @@ def test_prompts_call_stream(
     output = ""
     for chunk in response:
         assert chunk is not None
+        chunk = json.loads(chunk)
         assert chunk.output is not None
         assert chunk.id is not None
         assert chunk.prompt_id is not None