Unsafe transforms are being used?

While fixing #64 I noticed that the last meaningful change on `Products/PortalTransforms/unsafe_transforms/build_transforms.py` is from 2009 ⚠️ 

There are no tests covering that module either, deleting it and running `tox -e test` happily passes 😓 

Is that something still being used by anyone? Care to contribute tests for it? Should we remove it? 🤔 