Update action.yml

[glenn-jocher]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Streamlined the way Prettier formats Markdown files in the repository.

📊 Key Changes

• Simplified Prettier commands for formatting Markdown (*.md) files.
• Adjusted shell commands to find and format Markdown files more efficiently.

🎯 Purpose & Impact

• Efficiency: 🛠 Cleaned up shell commands to streamline the formatting process.
• Consistency: 📄 Ensures consistent code style in Markdown files, making them easier to read and maintain.
• Performance: ⚡ Reduces the potential for errors and improves automation efficiency by simplifying the commands.