atest/genrunner.py: don't write un-necessary empty line to end
atest/genrunner.py: don't write un-necessary empty line to end

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