You tried to plan twice at t/perlcritic.t line 9.
# Looks like your test died before it could output anything.

##</code><code>##

1..1
ok 1 - Test::Perl::Critic for "blib/lib/GD/Graph/Thermometer.pm"

##</code><code>##

#!/usr/bin/perl -w
use Test::More qw(no_plan);

SKIP:
{

  eval 'use Test::Perl::Critic';
  skip('because Test::Perl::Critic required for these tests.',1) if $@;
  Test::Perl::Critic::all_critic_ok();

}


##</code><code>##

1..1
ok 1 - Test::Perl::Critic for "blib/lib/GD/Graph/Thermometer.pm"

##</code><code>##

1..0 # Skip because Test::Perl::Critic required for these tests