[BUG] Locally run tutorials do not show same results as web tutorials

[twobitunicorn]

Describe the bug
Running the tutorials (eg. https://pytorch-forecasting.readthedocs.io/en/stable/tutorials/ar.html) locally do not produce the same results as the website tutorial. In the N-Beats example, the graphs all show really nice and tidy predictions. When run on a modern mac m2 or on the current google collab all the predictions are flat and are somewhat indicative of a linear pattern, but no where near as accurate as the online tutorials.

[fkiraly]

I believe this PR addressed that: #1750

This was approved but we forgot to merge for 1.3.0 - perhaps because it was not linked to an issue.

Merged now.

[fkiraly]

Appreciated if you could check if this is a fix, and report back. (if yes, close; if no, update and ping the author of #1750)

[twobitunicorn]

Hey all. Just ran against the examples and we are looking great!