edit Units.compoundUnitsRaw test to match new overloading of addUnit()
edit Units.compoundUnitsRaw test to match new overloading of addUnit()

MichaelClerx/libcellml,nickerso/libcellml,cellml/libcellml,hsorby/libcellml,MichaelClerx/libcellml,nickerso/libcellml,cellml/libcellml,nickerso/libcellml,libcellml/buildbot-testing,nickerso/libcellml,cellml/libcellml,libcellml/buildbot-testing,hsorby/libcellml,hsorby/libcellml,MichaelClerx/libcellml,hsorby/libcellml,cellml/libcellml