title: Rspec and Chrome/headless flag
body: <p>I've got headless Chrome and Chrome working for my Rspec tests. I want a flag to switch between the two so I can see the tests happen when I want and hide them when I don't. How can I implement something like:</p>
  
  <pre><code>rspec --headless
  </code></pre>
  
  <p>Right now I just have this secret tied to a <code>.env</code> var:</p>
  
  <pre><code>Capybara.javascript_driver = Rails.application.secrets.headless ? :headless_chrome : :chrome
  </code></pre>