Update docstring to clarify download_root and output_dir

faster_whisper/utils.py

@@ -45,7 +45,7 @@ def download_model(
       size: Size of the model to download (tiny, tiny.en, base, base.en, small, small.en,
         medium, medium.en, large-v1, or large-v2).
       output_dir: Directory where the model should be saved. If not set, the model is saved in
-        the standard Hugging Face cache directory.
+        the cache directory.
       local_files_only:  If True, avoid downloading the file and return the path to the local
         cached file if it exists.
       cache_dir: Path to the folder where cached files are stored.