t1600-index: remove unnecessary redirection

In a helper function in the 't1600-index.sh' test script the stderr
of a 'git add' command is redirected to its stdout, but its stdout is
not redirected anywhere.  So apparently this redirection is
unnecessary, remove it.

Signed-off-by: SZEDER Gábor <[email protected]>
Acked-by: Derrick Stolee <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: szeder

t/t1600-index.sh

@@ -79,7 +79,7 @@ test_index_version () {
 		else
 			unset GIT_INDEX_VERSION
 		fi &&
-		git add a 2>&1 &&
+		git add a &&
 		echo $EXPECTED_OUTPUT_VERSION >expect &&
 		test-tool index-version <.git/index >actual &&
 		test_cmp expect actual