Merge pull request #25775 from richard28039:4.x

Add yolov8l.onnx to samples #25775

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- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
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- [ ] There is a reference to the original bug report and related work
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      Patch to opencv_extra has the same branch name.
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Hello, I noticed that the /samples/dnn/models.yml said it should be used for all yolov8 models, but the YOLOv8l is not included in the file, so I added it to the file, thanks.
![image](https://github.com/opencv/opencv/assets/89371302/7a7b0090-ef4c-478d-8f24-7d99260fe0c9)

samples/dnn/models.yml

@@ -76,6 +76,20 @@ yolov8m:
   background_label_id: 0
   sample: "yolo_detector"
 
+yolov8l:
+  load_info:
+    url: "https://github.com/CVHub520/X-AnyLabeling/releases/download/v0.1.0/yolov8l.onnx"
+    sha1: "462df53ca3a85d110bf6be7fc2e2bb1277124395"
+  model: "yolov8l.onnx"
+  mean: 0.0
+  scale: 0.00392
+  width: 640
+  height: 640
+  rgb: true
+  classes: "object_detection_classes_yolo.txt"
+  background_label_id: 0
+  sample: "yolo_detector"
+
 # YOLO4 object detection family from Darknet (https://github.com/AlexeyAB/darknet)
 # YOLO object detection family from Darknet (https://pjreddie.com/darknet/yolo/)
 # Might be used for all YOLOv2, TinyYolov2, YOLOv3, YOLOv4 and TinyYolov4