Update ultralytics-thop version to 0.2.8

[glenn-jocher]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Small version update to the thop package.

📊 Key Changes

• Updated the __version__ variable from "0.2.7" to "0.2.8".

🎯 Purpose & Impact

• Purpose: This change likely includes minor bug fixes, improvements, or new features that are not detailed in the diff but are necessary to increment the version number.
• Impact: Users will now receive the latest enhancements or fixes when they use version 0.2.8, improving overall stability and functionality of the thop package.

🎉 This update helps ensure you are working with the most up-to-date version of the tool!