t3040: remove stale note

This comment was most likely a "note to self" during the development of
1c3e5c4ebc (Tests for core subproject support, 2007-04-19) and is
neither needed nor comprehensible at this point. Let's remove it.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t3040-subprojects-basic.sh

@@ -79,7 +79,4 @@ test_expect_success 'checkout in superproject' '
 	git diff-index --exit-code --raw --cached save -- sub1
 '
 
-# just interesting what happened...
-# git diff --name-status -M save master
-
 test_done