Update the README effective robustness figure with new OpenCLIP models

[carlini]

The effective robustness figure

https://raw.githubusercontent.com/mlfoundations/open_clip/main/docs/effective_robustness.png

only shows the old YFCC OpenCLIP Models. It would be great to show the new OpenCLIP Models on this same figure to both show (1) they're as good as or better than OpenAI's models, and (2) they have effective robustness on ImageNetV2.