Add test in validator showing units equivalence validation not working.
Add test in validator showing units equivalence validation not working.

hsorby/libcellml,nickerso/libcellml,nickerso/libcellml,hsorby/libcellml,cellml/libcellml,cellml/libcellml,cellml/libcellml,nickerso/libcellml,nickerso/libcellml,cellml/libcellml,hsorby/libcellml,hsorby/libcellml