Gettextize the "You have not concluded your merge messages. A test in
t3030-merge-recursive.sh explicitly checked for this message. Change
it to skip the test under GETTEXT_POISON=YesPlease.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>