📚 Add basic PwBaseWorkChain documentation

[mbercx]

Mainly testing if the docs do build properly still for branches on the aiidateam repository.

[mbercx]

Note: closing the PR and reopening it fixed the RTD build issue. I'm assuming this forced Github to update the references again, which can then be properly picked up by RTD.

[mbercx]

Now it's failing at the checkout stage...

git clone --depth 1 https://github.com/aiidateam/aiida-quantumespresso.git
git fetch origin --force --prune --prune-tags --depth 50 pull/1074/head:external-1074
git checkout --force cadfc7fd310c20e4a34a51526dd5c0f22605508d

With the error:

fatal: reference is not a tree: cadfc7fd310c20e4a34a51526dd5c0f22605508d

[mbercx]

It seems that the RTD build starts too fast somehow. I can reproduce the error locally, and I see that the latest commit is missing from the log. If I wait a bit longer, the checkout command does work. At that point I can rebuild the documentation on RTD and all is well.

[mbercx]

Tried to integrate a change in the .readthedocs.yaml file to make the build wait a bit, but that didn't work. I suppose we could add it to the CI, but maybe this is a temporary issue. For now I guess we can just wait a bit and retrigger the RTD build.

[bastonero]

Thanks a lot @mbercx !

This is really needed, and thanks for pushing it. I think it would be great to have at least two or three how-tos:

1. One showing how to get the builder and "fill it up" (or even just creating an inputs dictionary with the minimal structure
2. The second showing how to easily get it using the get_builder_from_protocol
3. The third showing how to override the default inputs

Then we should also add an extra how-to page to just explain in general the usage of the get_builder_from_protocol and how to get other info about protocols.

[mbercx]

Haha, thanks for the comments @bastonero! This was really just a super initial draft to test why the RTD build was failing, but yes I did want to get started on this, documentation should be a priority after we merge as many of the open PRs as possible I think.

I'll try to have a more solid crack at adding these first parts later this week!