tests: don't assume a .git/info for .git/info/grafts

Change those tests that assumed that a .git/info directory would be
created for them when writing .git/info/grafts to explicitly create
the directory.

Do this using the new "TEST_CREATE_REPO_NO_TEMPLATE" facility, and use
"mkdir" instead of "mkdir -p" to assert that we don't have the
.git/info already. An exception to this is the "with grafts" test in
"t6001-rev-list-graft.sh". There we're modifying our ".git" state in a
for-loop, in lieu of refactoring that more extensively let's use
"mkdir -p" there.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/annotate-tests.sh b/t/annotate-tests.sh
index 09e86f9..71f391f 100644
--- a/t/annotate-tests.sh
+++ b/t/annotate-tests.sh
@@ -149,7 +149,7 @@
 
 test_expect_success 'blame huge graft' '
 	test_when_finished "git checkout branch2" &&
-	test_when_finished "rm -f .git/info/grafts" &&
+	test_when_finished "rm -rf .git/info" &&
 	graft= &&
 	for i in 0 1 2
 	do
@@ -164,6 +164,7 @@
 			graft="$graft$commit " || return 1
 		done
 	done &&
+	mkdir .git/info &&
 	printf "%s " $graft >.git/info/grafts &&
 	check_count -h 00 01 1 10 1
 '