Fix video serializing in client

[freddyaboulton]

Description

Video components in latest gradio version were not able to be serialized because:

1. VideoSerializer was not included in Serializer map. Solution is to include subclasses as well.
2. There was an isinstance(x, tuple) check in deserialize but tuples don't exist in json so when we load the json they get converted to lists.

Should fix the tests on main.

Checklist:

• I have performed a self-review of my own code
• I have added a short summary of my change to the CHANGELOG.md
• My code follows the style guidelines of this project
• I have commented my code in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

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[gradio-pr-bot]

All the demos for this PR have been deployed at https://huggingface.co/spaces/gradio-pr-deploys/pr-3860-all-demos

[abidlabs]

Thanks @freddyaboulton! Will review properly in a few hours when I'm back at my computer. But earlier today, I tested a Space with a video output, and it seemed to work fine:

from gradio_client import Client

c = Client("abidlabs/cinemascope")
c.predict("a cat jumping")

Is this PR fixing something else?

[freddyaboulton]

The issue is only affecting gradio 3.26.0 and above I believe. CI is red on main right now because VideoSerializable is not present in the serializer dict!

[abidlabs]

Ideally we traverse all descendant subclasses recursively

[abidlabs]

Haven’t tested but code looks good, feel free to merge

[freddyaboulton]

No rush!

[abidlabs]

Tested, works great on old and new Spaces with videos, thanks @freddyaboulton! Let's release a new version of the gradio client to get this out