disabling Telemetry did not help the Docker build

lib/labelmaker/application.ex

@@ -8,7 +8,7 @@ defmodule Labelmaker.Application do
   @impl true
   def start(_type, _args) do
     children = [
-      # LabelmakerWeb.Telemetry,
+      LabelmakerWeb.Telemetry,
       {DNSCluster, query: Application.get_env(:labelmaker, :dns_cluster_query) || :ignore},
       {Phoenix.PubSub, name: Labelmaker.PubSub},
       # Start a worker by calling: Labelmaker.Worker.start_link(arg)

lib/labelmaker_web/endpoint.ex

@@ -38,7 +38,7 @@ defmodule LabelmakerWeb.Endpoint do
     cookie_key: "request_logger"
 
   plug Plug.RequestId
-  # plug Plug.Telemetry, event_prefix: [:phoenix, :endpoint]
+  plug Plug.Telemetry, event_prefix: [:phoenix, :endpoint]
 
   plug Plug.Parsers,
     parsers: [:urlencoded, :multipart, :json],

lib/labelmaker_web/router.ex

@@ -27,18 +27,18 @@ defmodule LabelmakerWeb.Router do
   # end
 
   # Enable LiveDashboard in development
-  # if Application.compile_env(:labelmaker, :dev_routes) do
+  if Application.compile_env(:labelmaker, :dev_routes) do
-  #   # If you want to use the LiveDashboard in production, you should put
+    # If you want to use the LiveDashboard in production, you should put
-  #   # it behind authentication and allow only admins to access it.
+    # it behind authentication and allow only admins to access it.
-  #   # If your application does not have an admins-only section yet,
+    # If your application does not have an admins-only section yet,
-  #   # you can use Plug.BasicAuth to set up some basic authentication
+    # you can use Plug.BasicAuth to set up some basic authentication
-  #   # as long as you are also using SSL (which you should anyway).
+    # as long as you are also using SSL (which you should anyway).
-  #   import Phoenix.LiveDashboard.Router
+    import Phoenix.LiveDashboard.Router
-  #
+
-  #   scope "/dev" do
+    scope "/dev" do
-  #     pipe_through :browser
+      pipe_through :browser
-  #
+
-  #     live_dashboard "/dashboard", metrics: LabelmakerWeb.Telemetry
+      live_dashboard "/dashboard", metrics: LabelmakerWeb.Telemetry
-  #   end
+    end
-  # end
+  end
 end

mix.exs

@@ -47,8 +47,8 @@ defmodule Labelmaker.MixProject do
        app: false,
        compile: false,
        depth: 1},
-      # {:telemetry_metrics, "~> 1.0"},
+      {:telemetry_metrics, "~> 1.0"},
-      # {:telemetry_poller, "~> 1.0"},
+      {:telemetry_poller, "~> 1.0"},
       {:gettext, "~> 0.26"},
       {:jason, "~> 1.2"},
       {:dns_cluster, "~> 0.1.1"},