Fix average_score

server.py

@@ -147,7 +147,7 @@ class LeaderboardServer:
                 if category == "overall":
                     for c in win_score:
                         local_results[c] = win_score[c]
-                    local_results["average_score"] = sum(win_score[c]) / len(win_score[c])
+                    local_results["average_score"] = sum(win_score) / len(win_score)
                 else:
                     local_results["average_score"] = win_score[category]