Git.pm: fix example in command_close_bidi_pipe documentation

File handle goes as the first argument when calling print on it.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/perl/Git.pm b/perl/Git.pm
index bbb753a..11f310a 100644
--- a/perl/Git.pm
+++ b/perl/Git.pm
@@ -418,7 +418,7 @@
 is:
 
 	my ($pid, $in, $out, $ctx) = $r->command_bidi_pipe('cat-file --batch-check');
-	print "000000000\n" $out;
+	print $out "000000000\n";
 	while (<$in>) { ... }
 	$r->command_close_bidi_pipe($pid, $in, $out, $ctx);