README evaluate openpi link directs to 404

<img width="1122" height="597" alt="Image" src="https://github.com/user-attachments/assets/556a25b1-4070-4d79-8263-fbb8643741e3" />

<img width="1452" height="512" alt="Image" src="https://github.com/user-attachments/assets/a84d2312-392c-463a-a258-d3e2e15edc94" />

I will find the way to evaluate pi on vlabench anyway, but I think it would be great if you could check and fix the link. Thank you.