Give empty STDIN to processes so they die faster if they want input

lib/TestCpanInc.pm

@@ -56,7 +56,8 @@ sub run_cpanm {
     my @cmd = (qw/perlbrew exec --with/, $perlbrew_env, qw|cpanm --reinstall --verbose |, $module);
 
     my $out;
-    my $h = harness \@cmd, '>&', \$out, timeout(10*60); # timeout after 10 minutes
+    my $in='';
+    my $h = harness \@cmd, '<', \$in, '>&', \$out, timeout(10*60); # timeout after 10 minutes
     eval {
       $h->start();