Some have found the wording of the description to be somewhat ambiguous with respect to when it is desirable to use test_must_fail instead of "! <git-command>". Tweak the wording somewhat to hopefully clarify that it is _because_ test_must_fail can detect segmentation fault that it is desirable to use it instead of "! <git-command>".
Signed-off-by: Brandon Casey <firstname.lastname@example.org> Signed-off-by: Junio C Hamano <email@example.com>