Remove website jsons from git and add script to pnpm build

[aliabd]

This PR removes the annoying website jsons from git and adds the generation script to the pnpm command. That way you don't have to run the script anymore or commit jsons. I also overrid the vercel build command to run pnpm build instead of vite build.

Closes this in #4804:

• Stop tracking jsons in git

[vercel]

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Name	Status	Preview	Updated (UTC)
gradio	✅ Ready (Inspect)	Visit Preview	Jul 24, 2023 3:33pm

[gradio-pr-bot]

All the demos for this PR have been deployed at https://huggingface.co/spaces/gradio-pr-deploys/pr-4953-all-demos

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You can install the changes in this PR by running:

pip install https://gradio-builds.s3.amazonaws.com/4b0e98e40ac94b8c43ba2158d02ec0ce27366881/gradio-3.38.0-py3-none-any.whl

[gradio-pr-bot]

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[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
website	minor

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With the following changelog entry.

Remove website jsons from git and add script to pnpm build

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