enable ANSI colors in debug adapter

the output looks correctly in recent VSCode
Fixes elixir-lsp/vscode-elixir-ls#422

Author: lukaszsamson

apps/debug_adapter/lib/debug_adapter.ex

@@ -7,6 +7,7 @@ defmodule ElixirLS.DebugAdapter do
     Application.load(:erts)
     Application.put_env(:elixir, :ansi_enabled, false)
     WireProtocol.intercept_output(&Output.debuggee_out/1, &Output.debuggee_err/1)
+    Application.put_env(:elixir, :ansi_enabled, true)
     Launch.start_mix()
 
     if Version.match?(System.version(), ">= 1.15.0-dev") do

apps/debug_adapter/lib/debug_adapter/server.ex

@@ -1730,9 +1730,6 @@ defmodule ElixirLS.DebugAdapter.Server do
       Mix.Task.run("loadconfig")
     end
 
-    # make sure ANSI is disabled
-    Application.put_env(:elixir, :ansi_enabled, false)
-
     unless "--no-compile" in task_args or "--no-mix-exs" in task_args do
       case Mix.Task.run("compile", ["--ignore-module-conflict", "--return-errors"]) do
         {:error, diagnostics} ->