title: Rails: Unable to overwrite config.action_cable.url
body: <p>I am trying to over write the <code>config.action_cable.url</code> to something like this <code>config.action_cable.url=wss://test.domain.com/staging/cable</code></p>
  <p>but when i load my application i still see error message <code>WebSocket connection to wss://test.domain.com/cable</code></p>
  <p>Any thoughts on how i can do this would be really great.
  Thanks.</p>