t0005: fix broken &&-chains

The ":" noop command always returns true, so it is fine to
include these lines in an &&-chain (and it appeases
--chain-lint).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t0005-signals.sh

@@ -40,12 +40,12 @@ test_expect_success 'create blob' '
 '
 
 test_expect_success !MINGW 'a constipated git dies with SIGPIPE' '
-	OUT=$( ((large_git; echo $? 1>&3) | :) 3>&1 )
+	OUT=$( ((large_git; echo $? 1>&3) | :) 3>&1 ) &&
 	test "$OUT" -eq 141
 '
 
 test_expect_success !MINGW 'a constipated git dies with SIGPIPE even if parent ignores it' '
-	OUT=$( ((trap "" PIPE; large_git; echo $? 1>&3) | :) 3>&1 )
+	OUT=$( ((trap "" PIPE; large_git; echo $? 1>&3) | :) 3>&1 ) &&
 	test "$OUT" -eq 141
 '