Add failing spec for apache 2.4 virtual host changes.
user
```ruby
require 'spec_helper'

describe 'config-driven-helper::apache-sites' do
  before do
    stub_command("/usr/sbin/apache2 -t").and_return(true)
  end

  context 'apache 2.2' do
    cached(:chef_run) do
      ChefSpec::SoloRunner.new do |node|
        node.set['apache']['version'] = '2.2'
        node.set['apache']['sites']['hello']['docroot'] = '/var/www/hello.example.com'
        node.set['apache']['sites']['hello']['server_name'] = 'hello.example.com'
      end.converge(described_recipe)
    end

    it 'will write out apache 2.2 configuration when 2.2 is in use' do
      expect(chef_run).to render_file('/etc/apache2/sites-available/hello.example.com').with_content('Order allow,deny')
    end

    it 'will not write out apache 2.4 configuration when 2.2 is in use' do
      expect(chef_run).to_not render_file('/etc/apache2/sites-available/hello.example.com').with_content('Require all granted')
    end
  end

  context 'apache 2.4' do
    cached(:chef_run) do
      ChefSpec::SoloRunner.new do |node|
        node.set['apache']['version'] = '2.4'
        node.set['apache']['sites']['hello']['docroot'] = '/var/www/hello.example.com'
        node.set['apache']['sites']['hello']['server_name'] = 'hello.example.com'
      end.converge(described_recipe)
    end

    it 'will write out apache 2.4 configuration when 2.4 is in use' do
      expect(chef_run).to render_file('/etc/apache2/sites-available/hello.example.com').with_content('Require all granted')
    end

    it 'will not write out apache 2.2 configuration when 2.4 is in use' do
      expect(chef_run).to_not render_file('/etc/apache2/sites-available/hello.example.com').with_content('Order allow,deny')
    end
  end
end
```
assistant