create model card for astroGPT (#6960)
create model card for astroGPT (#6960)

* create model card for astroGPT

* Hotlink to actual image file

Co-authored-by: Julien Chaumond <a2e75dc0f7a441a5f83dcee1a3f7492a8c3d1d78@gmail.com>
huggingface/transformers,huggingface/pytorch-transformers,huggingface/transformers,huggingface/transformers,huggingface/transformers