Add minitest/hell and parallelize_me! to the plugin tests.

We already do this in test/helper.rb so we might as well do it here.

Signed-off-by: Ryan Davis <zenspider@chef.io>

lib/plugins/shared/core_plugin_test_helper.rb

@@ -12,6 +12,8 @@ require 'tmpdir'
 require 'pathname'
 require 'forwardable'
 
+require 'inspec/plugin/v2'
+
 # Configure Minitest to expose things like `let`
 class Module
   include Minitest::Spec::DSL