Update links.yml to --scheme https

[glenn-jocher]

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🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improving link checking security in GitHub workflows with enforced HTTPS.

📊 Key Changes

• Enforced the use of HTTPS by adding --scheme 'https' to the lychee command in GitHub Actions workflows.
• This change applies to two separate instances within the links.yml file.

🎯 Purpose & Impact

• 🛡️ Enhanced Security: Enforcing HTTPS improves the security of link checking, ensuring that all URLs are accessed over a secure connection.
• 🔒 Preventing MiTM Attacks: It helps prevent Man-in-the-Middle (MiTM) attacks that can occur when using non-secure HTTP connections.
• 👁️ User Confidence: Users can trust that the links checked in the Ultralytics repository maintain high-security standards, increasing overall trust in the integrity of the repository.