Fix scipy 1.12 deprecation for scipy.ndimage imports

[mweinelt]

Fixes two warnings

Please import shift from the scipy.ndimage namespace; the scipy.ndimage.interpolation namespace is deprecated and will be removed in SciPy 2.0.0.

and

Please import convolve from the scipy.ndimage namespace; the scipy.ndimage.filters namespace is deprecated and will be removed in SciPy 2.0.0.