Use hf auth login instead of deprecated huggingface-cli in leaderboard guide (#2621)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

Author: davanstrien

docs/hub/leaderboard-data-guide.md

@@ -41,7 +41,7 @@ for entry in leaderboard[:5]:
 ```
 
 > [!TIP]
-> `huggingface_hub` uses your cached token by default. For gated benchmark datasets, make sure you are logged in (`huggingface-cli login`) or pass a token explicitly:
+> `huggingface_hub` uses your cached token by default. For gated benchmark datasets, make sure you are logged in (`hf auth login`) or pass a token explicitly:
 > ```python
 > leaderboard = api.get_dataset_leaderboard("gated/benchmark", token="hf_...")
 > ```