Model zoo link fixes (#18668)

Author: ptelman

docs/machine-learning/tutorials/object-detection-onnx.md

@@ -98,7 +98,7 @@ Now that you have a general understanding of what ONNX is and how Tiny YOLOv2 wo
 
 1. Copy the `assets` directory into your *ObjectDetection* project directory. This directory and its subdirectories contain the image files (except for the Tiny YOLOv2 model, which you'll download and add in the next step) needed for this tutorial.
 
-1. Download the [Tiny YOLOv2 model](https://onnxzoo.blob.core.windows.net/models/opset_8/tiny_yolov2/tiny_yolov2.tar.gz) from the [ONNX Model Zoo](https://github.com/onnx/models/tree/master/vision/object_detection_segmentation/tiny_yolov2), and unzip.
+1. Download the [Tiny YOLOv2 model](https://onnxzoo.blob.core.windows.net/models/opset_8/tiny_yolov2/tiny_yolov2.tar.gz) from the [ONNX Model Zoo](https://github.com/onnx/models/tree/master/vision/object_detection_segmentation/tiny-yolov2), and unzip.
 
     Open the command prompt and enter the following command: