Update index.md

Author: ChrisRackauckas

docs/src/index.md

@@ -211,7 +211,7 @@ Julia packages.
 ## Contributing
 
   - Please refer to the
-    [SciML ColPrac: Contributor's Guide on Collaborative Practices for Community Packages](https://github.com/SciML/ColPrac/blob/master/README.md)
+    [SciML ColPrac: Contributor's Guide on Collaborative Practices for Community Packages](https://github.com/SciML/ColPrac)
     for guidance on PRs, issues, and other matters relating to contributing to SciML.
 
   - See the [SciML Style Guide](https://github.com/SciML/SciMLStyle) for common coding practices and other style decisions.