demidenm/PyReliMRI: Make bool when expected for dice, jaccard, tetrachor

Dice, Jaccard and Tetrachoric correlations expect boolean values, 1/0 (T/F). When non-boolean values are provided this will impact the resulting computing. Added a bool enforcement following thresholding for these three components.

# Imgs must be 1/0 binary images, ensure correct format for each similarity type
 if similarity_type.casefold() in ['dice', 'jaccard', 'tetrachoric']:
     # Binarize input for these metrics
     imgdata = imgdata.astype(bool)