Error while rendering notebooks on Github; problem with widgets

[AgnieszkaZaba]

After rerunning this notebook: https://github.com/open-atmos/PyMPDATA/blob/main/examples/PyMPDATA_examples/advection_diffusion_2d/advection-diffusion-2d.ipynb, there is still problem with rendering on GitHub.

[slayoo]

Thanks @AgnieszkaZaba !

first of all, we should come up with automated way of detecting this issue on CI (in PyMPDATA, PyPartMC and PySDM), and then of course also fix it