Doc building error

[mjwen]

Describe the bug

Docs are not properly built; there are errors like ModuleNotFound in the below and many other pages:
https://kliff.readthedocs.io/en/latest/introduction/Dataset.html

@ipcamit can you please help to fix this?

I believe https://github.com/openkim/kliff/blob/main/docs/requirements-docs.txt needs to be updated.

[ipcamit]

Sure. Will look into it.

[ipcamit]

This is harder then thought! spent entire day yesterday, but the issue is that the conda env that rtd creates is broken. Hence could not install models. Will spend some more time digging into it.