Fix deprecated scipy.ndimage import paths

[evertdeman]

I am getting some warning like

../usr/local/lib/python3.10/dist-packages/batchgenerators/augmentations/utils.py:23
  /usr/local/lib/python3.10/dist-packages/batchgenerators/augmentations/utils.py:23: DeprecationWarning: Please use `label` from the `scipy.ndimage` namespace, the `scipy.ndimage.measurements` namespace is deprecated.
    from scipy.ndimage.measurements import label as lb

this should fix that

[evertdeman]

Ah, I see there is another PR open for this: #108

Any reason we should not merge this?