Update app.py

app.py

@@ -675,5 +675,5 @@ with gr.Blocks(css=css, theme=gr.themes.Soft()) as demo:
     )
 
 if __name__ == "__main__":
-    head = "<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r128/three.min.js"></script>"
+    head = '<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r128/three.min.js"></script>'
     demo.launch(head=head)