Fixes streaming event race condition

[aliabid94]

Happened because of how we were closing event streams. Added a test that blasts lots of events rapidly so we don't run into this again. Test by running demo/rapid_generation on main and this branch.

Fixes: #7921

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/9d8da6384503bddbe8ee5097489d1f93f5e388db/gradio-4.25.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@9d8da6384503bddbe8ee5097489d1f93f5e388db#subdirectory=client/python"

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This Pull Request includes changes to the following packages.

Package	Version
@gradio/client	patch
gradio	patch

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Fixes streaming event race condition

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[freddyaboulton]

Nice fix @aliabid94 !

[yvrjsharma]

I can confirm that I no longer see the issue in the duplicated (private atm) mPLUGOwl/Doc Space when using the gradio wheels from this PR. Thanks @aliabid94 !

[pngwn]

Can you explain what the race condition is here? It isn't obvious from the code or tests.

[pngwn]

Looks good otherwise! Thanks @aliabid94!

[aliabid94]

race condition was that sometimes the client would receive the close_stream event from the backend before it had finished processing pending callbacks. This would cause the callback to be called with close_stream, but we shouldn't be calling the callback with that message, as would cause issues with apply_diff_stream

[dawoodkhan82]

Thanks for fixing @aliabid94

[keenranger]

This helped me streaming agent a lot! TY!