Build callbacks do not fire for module registration

[alexmg]

This issue is present in Autofac 4.5.

[Fact]
public void BuildCallbacksInvokedWhenRegisteredInModuleLoad()
{
	var module = new BuildCallbackModule();

	var builder = new ContainerBuilder();
	builder.RegisterModule(module);
	builder.Build();

	Assert.Equal(2, module.Called);
}

public class BuildCallbackModule : Module
{
	public int Called { get; private set; }

	protected override void Load(ContainerBuilder builder)
	{
		void BuildCallback(IContainer c)
		{
			Called++;
		}

		builder.RegisterBuildCallback(BuildCallback)
			.RegisterBuildCallback(BuildCallback);
	}
}