Mac CI won't execute electric field output

[lilyminium]

The cell where the model fails with the error (PR #131):

=================================== FAILURES ===================================
_ examples/train-gnn-to-electric-field/train-gnn-to-electric-field.ipynb::Cell 13 _
[gw2] darwin -- Python 3.11.9 /Users/runner/micromamba/envs/openff-nagl-test/bin/python
Notebook cell execution failed
Cell 13: Timeout of 5 seconds exceeded waiting for output.

Input:
trainer = pl.Trainer(
    max_epochs=100,
    callbacks=[TQDMProgressBar()], # add progress bar
    accelerator="cpu"
)

trainer.fit(
    training_model,
    datamodule=training_model.create_data_module(verbose=False),
)

Ubuntu executes fine. It also executes fine on my Mac.

[lilyminium]

AFAICT the options here are:

• try to work out if I can skip executing that cell. Not optimal since it does execute fine on Ubuntu and is a good test of whether training the model works
• See if I can just skip that notebook on mac?
• Work out what a 'Timeout of 5 seconds exceeded waiting for output.' means, since I think that cell takes longer than 5 seconds even on Ubuntu. Is it that it's not writing to stderr/stdout for 5 seconds? If so, should the two lines be split up?
• Decrease the dataset even more to see if that speeds this cell up -- but this makes the example worse and I'm not sure gains us much

[lilyminium]

Turned off for now. Might be a problem GPU runners can solve.