Fix unclosed here document in t3301.sh

Commit 908a320 introduced  indentation
to here documents in t3301.sh. However in one place <<-EOF was missing
-, which broke this test when run with mksh-50d. This commit fixes it.

Signed-off-by: Kacper Kornet <draenog@pld-linux.org>
Acked-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t3301-notes.sh

@@ -658,7 +658,7 @@ test_expect_success '--show-notes=* adds to GIT_NOTES_DISPLAY_REF' '
 '
 
 test_expect_success '--no-standard-notes' '
-	cat >expect-commits <<EOF
+	cat >expect-commits <<-EOF &&
 		commit 2c125331118caba0ff8238b7f4958ac6e93fe39c
 		Author: A U Thor <author@example.com>
 		Date:   Thu Apr 7 15:18:13 2005 -0700