Fix the expired image link used in theme builder (#4944)
* fix the expired image link
* update CHANGELOG.md
* Update gradio/themes/app.py
change the image link same as the original one
Co-authored-by: Abubakar Abid <abubakar@huggingface.co>
* Update gradio/themes/app.py
change the image link same as the original one
Co-authored-by: Abubakar Abid <abubakar@huggingface.co>
* apply lint
* equalize the default image link with app.py
* equalize default image links in building theme
* equalize default image links in demo notebook
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Co-authored-by: Abubakar Abid <abubakar@huggingface.co>
