Minor: Change execution error message
Minor: Change execution error message

graphicore/fontbakery,graphicore/fontbakery,googlefonts/fontbakery,googlefonts/fontbakery,vitalyvolkov/fontbakery,googlefonts/fontbakery,moyogo/fontbakery,jessamynsmith/fontbakery,graphicore/fontbakery,vitalyvolkov/fontbakery,moyogo/fontbakery,moyogo/fontbakery,vitalyvolkov/fontbakery,davelab6/fontbakery