Fix another mistake

server.py

@@ -196,7 +196,7 @@ class LeaderboardServer:
         for category, tasks in tasks_per_category.items():
             abbreviation2name = {self.TASKS_METADATA[t]["abbreviation"]: self.TASKS_METADATA[t]["name"] for t in tasks}
             sorted_abbreviation2name = dict.fromkeys(sorted(abbreviation2name.keys()))
-            sorted_abbreviation2name.update(sorted_abbreviation2name)
+            sorted_abbreviation2name.update(abbreviation2name)
             category2abbreviation2name[category] = sorted_abbreviation2name
         
         return category2abbreviation2name