Correct names of variables in takeVariable test.
Correct names of variables in takeVariable test.

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