Tweaks to icon parameter in gr.Button()

[abidlabs]

When I was working with @dawoodkhan82 on adding avatar images, we realized that we should slightly change the way that we handle icons in gr.Button() as well. I've implemented that logic for gr.Button() here.

The main advantage of this approach is that we no longer do any preprocessing in the backend of the icon parameter in the __init__ of gr.Button(). This is important because @aliabid94 is working on unifying the __init__ and update() of each component so we should make both as simple as possible. As a bonus, this fixes: #5243

Made some tweaks to gr.Chatbot and gr.Dataset as well.

cc @hannahblair @dawoodkhan82

Feel free to wreck my frontend code.

Test code:

import gradio as gr

path = "cheetah.jpg"
url = "https://fastly.picsum.photos/id/322/200/300.jpg?hmac=q6h4jr1n6SrXrRCeqCblcexGQCfYmSXhr8Oo5EGoHIU"

with gr.Blocks() as demo:
    b1 = gr.Button(icon=path)
    b2 = gr.Button(icon=url)
    
    b2.click(lambda :gr.Button.update(icon=url, value="hello"), None, b1)
    b1.click(lambda :gr.update(icon=path, value="hi"), None, b2)    
    
demo.launch()

[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/2266ed5c10938dfb9b92d64a68568967bb094a8b/gradio-3.40.1-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@2266ed5c10938dfb9b92d64a68568967bb094a8b#subdirectory=client/python"

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/app	patch
@gradio/button	patch
@gradio/chatbot	patch
@gradio/upload	patch
gradio	patch

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Tweaks to icon parameter in gr.Button()

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[abidlabs]

Thanks @freddyaboulton @hannahblair I've addressed your comments. Let me know if you have other feedback!

[freddyaboulton]

Thanks for the refactor and fix @abidlabs !