Adds `examples_per_page` to `gr.ChatInterface` and allows `clear_btn` in `gr.Interface` to be hidden

[abidlabs]

A few small changes in this PR:

1. First, adds examples_per_page to gr.ChatInterface, closes: https://github.com/gradio-app/gradio/issues/8233. My original plan had been to add support for providing an instance of gr.Examples but this does not really make sense since a user can't provide the correct fn to examples since the example function is redefined internally. We also have the same examples_per_page argument in gr.Interface
2. I went through the arguments of gr.Interface to make sure that we have equivalent arguments in gr.ChatInterface and made a few other small tweaks, such as allowing clear_btn in gr.Interface to be set to None hiding it, similar to how the buttons in gr.ChatInterface. I believe there was an issue about this that we closed
3. Adds some docs to gr.ChatInterface guide

[gradio-pr-bot]

🪼 branch checks and previews

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/de1ee9ade13a340113cf73285f636a7e3a91236f/gradio-4.29.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@de1ee9ade13a340113cf73285f636a7e3a91236f#subdirectory=client/python"

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
gradio	minor

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With the following changelog entry.

Adds examples_per_page to gr.ChatInterface and allows clear_btn in gr.Interface to be hidden

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[yvrjsharma]

This is awesome; thanks for taking care of this feature request, @abidlabs ! 🙌 The examples_per_page argument is now working for me for the ChatInterface component as well 🥳

[abidlabs]

Thanks @yvrjsharma for confirming!