t / t8005 / sjis.txton commit tests: fix and add lint for non-portable head -c N (2a59a6e)
   1SJIS_NAME="\8eR\93c \91¾\98Y"
   2SJIS_MSG="\83u\83\8c\81[\83\80\82Ì\83e\83X\83g\82Å\82·\81B"