Fix Math Typesetting for torch.linalg.matrix_exp (#101363)
Fixes current the matrix_exp documentation typesetting which has an unescaped underscore.
It currently looks like this
<img width="540" alt="image" src="https://github.com/pytorch/pytorch/assets/3844846/cbff79c3-8c1a-4003-bee3-c4c97ae0e3a0">
With the fix, it looks like this
<img width="555" alt="image" src="https://github.com/pytorch/pytorch/assets/3844846/a24d9a3f-bbbd-4685-9244-2bc06872b966">
Pull Request resolved: https://github.com/pytorch/pytorch/pull/101363
Approved by: https://github.com/lezcano
