Fix file uploading in iOS

[hannahblair]

Description

For some reason, passing file/* to the input's accept attribute doesn't work in iOS, and greys out all the options. passing *(to indicate all files are allowed) does, so this PR passes * instead of file/* if the device is iOS. We could pass undefined, but * is just for clarity.

To test, I ran the file component demo locally, and ran the BrowserStack chrome extension with an iOS device to make sure this works!

Closes: #8547

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[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/7d3047ebc041ff0e15dba6ddc811553da4135d40/gradio-4.39.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@7d3047ebc041ff0e15dba6ddc811553da4135d40#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-builds.s3.amazonaws.com/7d3047ebc041ff0e15dba6ddc811553da4135d40/gradio-client-1.4.0.tgz

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/upload	patch
gradio	patch

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With the following changelog entry.

Fix file uploading in iOS

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[pngwn]

Why is safari like this.

Looks great and works from my testing! Thanks @hannahblair!

[hannahblair]

@pngwn not the first time safari has been annoying! #4071