Fix: file_types checking bug

[jasongzy]

Description

In the case the user specifies a file extension in file_types, we don't need to guess the mime type of the allowed file (which causes errors on unconventional file extensions). Instead, we can just check if the file extensions match.

Closes: #9646

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[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-pypi-previews.s3.amazonaws.com/ffceaffc1c2c3f38175e73e0670232af0cfe0486/gradio-5.0.2-py3-none-any.whl

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pip install "gradio-client @ git+https://github.com/gradio-app/gradio@ffceaffc1c2c3f38175e73e0670232af0cfe0486#subdirectory=client/python"

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🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
gradio	patch
gradio_client	patch

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Fix: file_types checking bug

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[freddyaboulton]

Thanks @jasongzy !