Deprecated `get_cmap` function was removed in Matplotlib 3.9.0

[NicolasGensollen]

Matplotlib 3.9.0 was released yesterday (May 16th 2024).

Among the breaking changes of their API is the removal of matplotlib.cm.get_cmap, see changelog here.

This function seems to only be used here:

clinica/clinica/pipelines/machine_learning/ml_utils.py

Line 125 in 7f7a0b4

cmap = cm.get_cmap("Paired", num_datasets)

We need to update this to use the new API.