grep: enable recurse-submodules to work on <tree> objects

diff --git a/t/t0021/rot13-filter.pl b/t/t0021/rot13-filter.pl
old mode 100755 (executable)
new mode 100644 (file)
index ae4c50f..4d5697e
--- a/t/t0021/rot13-filter.pl
+++ b/t/t0021/rot13-filter.pl
@@ -1,4 +1,3 @@
-#!/usr/bin/perl
 #
 # Example implementation for the Git filter protocol version 2
 # See Documentation/gitattributes.txt, section "Filter Protocol"
@@ -22,6 +21,7 @@
 
 use strict;
 use warnings;
+use IO::File;
 
 my $MAX_PACKET_CONTENT_SIZE = 65516;
 my @capabilities            = @ARGV;