fix #22131: bad diatonic transposition of Cb, Cbb
also B#, B## - and add test

transpose tests were not being run, it seems, but they do work, so I am
enabling them and adding a diatonic transpose test that includes a full
chromatic scale.
Merge pull request #596 from MarcSabatella/22131-transpose-cb

fix #22131: bad diatonic transposition of Cb, Cbb