Dataset link in tutorial.ipynb

[gioelemo]

The link in section 2.2 of the tutorial.ipynb file is not working:
Is pointing to: https://huggingface.co/datasets/IDEALLab/beams_2d_v0 put it should point to one of these:

• https://huggingface.co/datasets/IDEALLab/beams_2d_25_50_v0
• https://huggingface.co/datasets/IDEALLab/beams_2d_50_100_v0
• https://huggingface.co/datasets/IDEALLab/beams_2d_100_200_v0