libdoc tests: better error message when running fails
libdoc tests: better error message when running fails

ldtri0209/robotframework,fiuba08/robotframework,waldenner/robotframework,fiuba08/robotframework,waldenner/robotframework,ldtri0209/robotframework,fiuba08/robotframework,ldtri0209/robotframework,waldenner/robotframework,waldenner/robotframework,waldenner/robotframework,ldtri0209/robotframework,ldtri0209/robotframework,fiuba08/robotframework,fiuba08/robotframework