grep tests: move "grep binary" alongside the rest

Move the "grep binary" test case added in aca20dd558 ("grep: add test script for binary file handling", 2010-05-22) so that it lives alongside the rest of the "grep" tests in t781*. This would have left a gap in the t/700* namespace, so move a "filter-branch" test down, leaving the "t7010-setup.sh" test as the next one after that. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>