Merge pull request #25176 from cabelo:4.x

Added and tested yolov8s and yolov8n model #25176

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [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
- [X] The PR is proposed to the proper branch
- [X] There is a reference to the original bug report and related work
- [X] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [X] The feature is well documented and sample code can be built with the project CMake

Below is evidence of the test:
![yolos-n](https://github.com/opencv/opencv/assets/675645/f3bd19ae-85a4-4747-9fa9-f6e31257d2d5)

samples/dnn/models.yml

@@ -34,6 +34,36 @@ yolov8x:
   background_label_id: 0
   sample: "yolo_detector"
 
+yolov8s:
+  load_info:
+    url: "https://github.com/CVHub520/X-AnyLabeling/releases/download/v0.1.0/yolov8s.onnx"
+    sha1: "82cd83984396fe929909ecb58212b0e86d0904b1"
+  model: "yolov8s.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"
+
+yolov8n:
+  load_info:
+    url: "https://github.com/CVHub520/X-AnyLabeling/releases/download/v0.1.0/yolov8n.onnx"
+    sha1: "68f864475d06e2ec4037181052739f268eeac38d"
+  model: "yolov8n.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