Update HUB banner image

[glenn-jocher]

Passed through tinypng for filesize reduction

Signed-off-by: Glenn Jocher [email protected]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Update of image links in README files.

📊 Key Changes

• Changed the image source URL in the Chinese version of the README (README_cn.md).
• Updated the image source URL in the English version of the README (README.md).

🎯 Purpose & Impact

• Purpose: To ensure that the images in both README files are correctly displayed, improving the repository's presentation.
• Impact: Enhances visual appeal and user experience for visitors to the Ultralytics GitHub by providing a working link to the updated branding assets. No impact on the functionality of the software itself.