Code for step 4

Author: akoutmos

mix.exs

@@ -38,7 +38,8 @@ defmodule DockerElixir19Release.MixProject do
       {:phoenix_live_reload, "~> 1.2", only: :dev},
       {:gettext, "~> 0.11"},
       {:jason, "~> 1.0"},
-      {:plug_cowboy, "~> 2.0"}
+      {:plug_cowboy, "~> 2.0"},
+      {:observer_cli, "~> 1.5"}
     ]
   end
 end