Fix: add scope to auth when uploading the ragfile.

[Wasimhejazi]

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Fixes :
fixed the following error :

app-1      |     |   File "/usr/local/lib/python3.11/site-packages/vertexai/preview/rag/rag_data.py", line 467, in upload_file
app-1      |     |     raise RuntimeError("Failed in uploading the RagFile due to: ", e) from e
app-1      |     | RuntimeError: ('Failed in uploading the RagFile due to: ', RefreshError('invalid_scope: Invalid OAuth scope or ID token audience provided.', {'error': 'invalid_scope', 'error_description': 'Invalid OAuth scope or ID token audience provided.'}))

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[matthew29tang]

Can you sign the CLA? It is required for the PR

[Wasimhejazi]

@matthew29tang Sure, I've just signed it .

[matthew29tang]

The lint is failing, can you format the line as follows:

credentials, _ = auth.default(
    scopes=["https://www.googleapis.com/auth/cloud-platform"]
)