Update cache comments

[glenn-jocher]

For better readability

🛠️ PR Summary

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🌟 Summary

Improved clarity in the cache validation process within the YOLOv5 data loader.

📊 Key Changes

• Updated comments to better reflect what the code checks in the caching system.

🎯 Purpose & Impact

• 🔍 Clarity Increased: The change in comments helps developers and users understand that the cache version and hash need to match exactly for cache validation.
• 🛠️ Maintenance: Ensures the code's intent is communicated clearly, reducing potential confusion for future maintenance or contributions.
• ➕ Non-functional: This update does not change the behavior of the code but makes understanding the cache checking process more straightforward.