change contributing link

Signed-off-by: Inyong Hwang <inyong1020@gmail.com>

Author: inyong37

index.html

@@ -124,7 +124,7 @@ <h2 class="subheading-1 text-center mb-2 mb-lg-4 pb-2">COMMUNITY</h2>
                                         </a>
                                     </div>
                                     <div class="col-6 col-md-3">
-                                        <a href="https://github.com/onnx/onnx/blob/main/docs/CONTRIBUTING.md#development" target="_blank" class="card-4 community-card subheading-5 text-center px-3 py-3 text-white bold-text">
+                                        <a href="https://github.com/onnx/onnx/blob/main/CONTRIBUTING.md#development" target="_blank" class="card-4 community-card subheading-5 text-center px-3 py-3 text-white bold-text">
                                             Check out our contribution guide
                                         </a>
                                     </div>