Fix gr.Plot change/load events and plotly css loaded

[freddyaboulton]

Description

Closes: #10252
Closes: #9997

Can't repro #10252 but I have refactored the code to only load the plotly css once.

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🦄 change detected

This Pull Request includes changes to the following packages.

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@gradio/plot	patch
gradio	patch

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Fix gr.Plot change/load events and plotly css loaded

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[abidlabs]

Can you explain the rationale for adding the .load() event to gr.Plot()? Why are we adding .load() to a component?

[freddyaboulton]

Got my wires crossed for a second - backed this out

[abidlabs]

looks great @freddyaboulton! As a side note, I noticed that the Plot component has a .clear() event, which is never actually called. We should probably just remove that event since there's no built-in clear button for the Plot component

[freddyaboulton]

Thanks @abidlabs !