docs: update code formatting

README.md

@@ -46,6 +46,7 @@ from ultralytics import YOLO
 model = YOLO("https://huggingface.co/peterhdd/pothole-detection-yolov8/resolve/main/best.pt")
 results = model("your_image.jpg")
 results.show()
+```
 
 
 This model is part of a complete end-to-end pothole detection system including training, GPU inference, and a mobile application.