Train model for docs using GAP

[frostedoyster]

Fixes #235 by training a GAP model for the ASE example

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📚 Documentation preview 📚: https://metatrain--236.org.readthedocs.build/en/236/

[PicoCentauri]

In order that this works you also have to create the model as a pre_build step in at build.job inside the .readthedocs.yml. Basically copy the line of the tox.ini to the .readthedocs.yml and remove the {toxinidir}.

See

https://docs.readthedocs.io/en/stable/config-file/v2.html#build-jobs

for more details about the syntax.

[frostedoyster]

Merge