Merge pull request opencv#24496 from cabelo:yolov3

Add weights yolov3 in models.yml opencv#24496

### 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

I don't know if this action is necessary, or the previous PR scale for the brach master.

Thanks.

samples/dnn/models.yml

@@ -21,7 +21,7 @@ opencv_fd:
 # 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
-yolo:
+yolov4:
   load_info:
     url: "https://github.com/AlexeyAB/darknet/releases/download/darknet_yolo_v3_optimal/yolov4.weights"
     sha1: "0143deb6c46fcc7f74dd35bf3c14edc3784e99ee"
@@ -32,7 +32,7 @@ yolo:
   width: 416
   height: 416
   rgb: true
-  classes: "object_detection_classes_yolov4.txt"
+  classes: "object_detection_classes_yolo.txt"
   sample: "object_detection"
 
 yolov4-tiny:
@@ -46,7 +46,21 @@ yolov4-tiny:
   width: 416
   height: 416
   rgb: true
-  classes: "object_detection_classes_yolov4.txt"
+  classes: "object_detection_classes_yolo.txt"
+  sample: "object_detection"
+
+yolov3:
+  load_info:
+    url: "https://pjreddie.com/media/files/yolov3.weights"
+    sha1: "520878f12e97cf820529daea502acca380f1cb8e"
+  model: "yolov3.weights"
+  config: "yolov3.cfg"
+  mean: [0, 0, 0]
+  scale: 0.00392
+  width: 416
+  height: 416
+  rgb: true
+  classes: "object_detection_classes_yolo.txt"
   sample: "object_detection"
 
 tiny-yolo-voc: