Fix more attributes; nullable params

Author: andrewmy

Tests/AsyncListenerTest.php

@@ -8,6 +8,7 @@
 use Enqueue\Null\NullMessage;
 use Enqueue\Null\NullQueue;
 use Enqueue\Test\ClassExtensionTrait;
+use Enqueue\Test\ReadAttributeTrait;
 use Interop\Queue\Context;
 use Interop\Queue\Producer;
 use PHPUnit\Framework\MockObject\MockObject;
@@ -20,6 +21,7 @@
 class AsyncListenerTest extends TestCase
 {
     use ClassExtensionTrait;
+    use ReadAttributeTrait;
 
     public function testCouldBeConstructedWithContextAndRegistryAndEventQueueAsString()
     {

Tests/ContainerAwareRegistryTest.php

@@ -6,12 +6,14 @@
 use Enqueue\AsyncEventDispatcher\EventTransformer;
 use Enqueue\AsyncEventDispatcher\Registry;
 use Enqueue\Test\ClassExtensionTrait;
+use Enqueue\Test\ReadAttributeTrait;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\DependencyInjection\Container;
 
 class ContainerAwareRegistryTest extends TestCase
 {
     use ClassExtensionTrait;
+    use ReadAttributeTrait;
 
     public function testShouldImplementRegistryInterface()
     {