Update stale.yml

[glenn-jocher]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improvement of automated stale message workflow for better engagement with the Ultralytics community.

📊 Key Changes

• Updated the stale issue and pull request messages in the GitHub Actions stale workflow.
• Extended the message to encourage users to report new issues or suggest features and to contribute via pull requests.

🎯 Purpose & Impact

• Purpose: To make the automated messages more friendly and encouraging, providing clear guidance on how users can continue to engage with the project.
• Impact: Expected to improve community experiences and participation, reducing the chance of contributors feeling ignored and potentially increasing contributions and discussions around the project.