add colour picker unit tests

[hannahblair]

Description

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[gradio-pr-bot]

🪼 branch checks and previews

•	Name	Status	URL
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🦄	Changes	detected!	Details

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Install Gradio from this PR

pip install https://huggingface.co/buckets/gradio/pypi-previews/resolve/9c35915e5fdd7fbb565e40227b42682109895284/gradio-6.14.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@9c35915e5fdd7fbb565e40227b42682109895284#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-npm-previews.s3.amazonaws.com/9c35915e5fdd7fbb565e40227b42682109895284/gradio-client-2.2.0.tgz

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/colorpicker	minor
gradio	minor

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• add colour picker unit tests

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‼️ Changeset not approved. Ensure the version bump is appropriate for all packages before approving.

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