fix: rewire cell2mol dependency in requirements and pyproject

[liam-o-marsh]

and also removed docs/build from the repo? not sure why it was there in the first place, but I can't remember if we were supposed to remove it either
edit: this is no longer the case now that it has been rebased

[briling]

I thought we removed docs/build in #114

[briling]

also cell2mol's requirements are incompatible with ours i think https://github.com/lcmd-epfl/cell2mol/blob/40b32372d9a922afcf3e73c29df0430cf624508c/pyproject.toml

[briling]

have you checked if 3.9 and 3.11 installations work?

[briling]

also are you sure we need docs-build in all?

[liam-o-marsh]

er-
not yet and not yet

[liam-o-marsh]

...also I could have sworn I removed those new git commit IDs from the changes

[liam-o-marsh]

ok, so the new cell2mol commit is incompatible with python itself (due to the syntax of some recent type annotations)
but we can make the migration on py3.11

[briling]

zip(*iterables, strict=False)(https://docs.python.org/3/library/functions.html#zip)

Changed in version 3.10: Added the strict argument.

@liam-o-marsh so nothing works now... should we just drop 3.9?

[briling]

py3.11 passes all the tests

[briling]

nothing works

oh i know how to fix this

[briling]

okay I can redefine zip but pyscf 2.0 is also too old...

[briling]

okay I can fix a lot of thing but not cell2mol

[briling]

shall we keep python 3.9 compatibility fix ugly hacks of 4072f82? @liam-o-marsh @YAY-C

[liam-o-marsh]

hm...
I guess we should have at least one known-good commit that benefits from both our recent changes and py3.9 support, even without the cell2mol submodule.
we can probably queue removal of py3.9 for after the January event.

[briling]

okay! shall we merge this then?