Update utils.py

utils.py

@@ -63,10 +63,11 @@ SUBMIT_INTRODUCTION = """# Submit on MMEB Leaderboard Introduction
 ```json
 {
     "metadata": {
-        "Model": "<Model Name>",
-        "URL": "<Model URL>" or null,
-        "Model Size(B)": 1000 or null,
-        "Data Source": "Self-Reported",
+        "model_name": "<Model Name>",
+        "url": "<Model URL>" or null,
+        "model_size": <Model Size> or null,
+        "data_source": "Self-Reported",
+        ... ...
     },
     "metrics": {
         "image": {