Elixir: Don't autostart dependent applications

We wanted to include Wobserver in all our deployed applications but due to security considerations, it was necessary that it not run automatically (in order that the port on which it listens remain closed by default)

I spend about a day trying to get this to work without success.
Finally, this was what succeeded. In the mix.exs file, add the wobserver dependency to included applications:

included_applications: [ :wobserver]

This will prevent the application from getting autostarted.