Revert "chore: fix tests"

This reverts commit 67305a6ec8.

lib/ash/error/error.ex

@@ -370,7 +370,7 @@ defmodule Ash.Error do
     %{error | stacktrace: stacktrace || fake_stacktrace()}
   end
 
-  defp fake_stacktrace do
+  defp fake_stacktrace() do
     {:current_stacktrace, stacktrace} = Process.info(self(), :current_stacktrace)
     %Stacktrace{stacktrace: Enum.drop(stacktrace, 2)}
   end

test/resource/relationships/belongs_to_test.exs

@@ -309,7 +309,8 @@ defmodule Ash.Test.Resource.Relationships.BelongsToTest do
             %Ash.Error.Invalid{
               changeset: %{
                 errors: [
-                  %{path: [:post]} | _
+                  # there should not be a Ash.Error.Changes.Required error in this list
+                  %Ash.Error.Invalid{path: [:post]}
                 ]
               }
             }} =