chore: update download error message

[reidliu41]

What does this PR do?

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Actually, the incorrect token also will hit RepositoryNotFoundError, e.g.

$ llama model download --source huggingface --model-id Llama3.2-1B-Instruct:int4-qlora-eo8 --hf-token xx  ### xx is incorrect token
----RepositoryNotFoundError--->
usage: llama model download [-h] [--source {meta,huggingface}] [--model-id MODEL_ID]
                            [--hf-token HF_TOKEN] [--meta-url META_URL]
                            [--max-parallel MAX_PARALLEL] [--ignore-patterns IGNORE_PATTERNS]
                            [--manifest-file MANIFEST_FILE]
llama model download: error: Repository 'meta-llama/Llama-3.2-1B-Instruct-QLORA_INT4_EO8' not found on the Hugging Face Hub.

so update to:
 llama model download --source huggingface --model-id Llama3.2-1B-Instruct:int4-qlora-eo8 --hf-token xx
----RepositoryNotFoundError--->
usage: llama model download [-h] [--source {meta,huggingface}] [--model-id MODEL_ID]
                            [--hf-token HF_TOKEN] [--meta-url META_URL]
                            [--max-parallel MAX_PARALLEL] [--ignore-patterns IGNORE_PATTERNS]
                            [--manifest-file MANIFEST_FILE]
llama model download: error: Repository 'meta-llama/Llama-3.2-1B-Instruct-QLORA_INT4_EO8' not found on the Hugging Face Hub or incorrect Hugging Face token.

Test Plan

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[leseb]

Can't incorrect Hugging Face token be caught separately?

[reidliu41]

HfHubHTTPError << RepositoryNotFoundError(401 Client Error) << GatedRepoError(403 Client Error)
RepositoryNotFoundError inherit from HfHubHTTPError, it should cover to detect the incorrect token, but just say not found, seems cannot describe it better.(pls correct if i am wrong.)

https://github.com/huggingface/huggingface_hub/blob/290aa26f22d415853fd9e3560b9cc616821d2f73/src/huggingface_hub/errors.py#L174

[leseb]

Thanks for the explanation.