Remove streaming source sleep period

[glenn-jocher]

Negatively impacts YouTube inference but removes any lag on webcams/RTSP/RTMP etc.

Resolves #4465

🛠️ PR Summary

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🌟 Summary

Optimized video stream handling in YOLOv5 data loader for improved performance.

📊 Key Changes

• Removed the fixed sleep time based on frames per second (fps) in the video data loader.
• The sleep time after each frame is now set to 0.0 seconds.

🎯 Purpose & Impact

• 🚀 Purpose: This change aims to eliminate unnecessary delays when processing video streams, which can contribute to real-time performance.
• ✅ Impact: Users may experience faster video processing with reduced latency, making the YOLOv5 model more efficient for real-time applications like surveillance or live video analysis.