Add strict comparison null !== instead of ! (#1794)

Author: jderusse

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## NOT RELEASED
 
+### Changed
+
+- use strict comparison `null !==` instead of `!`
+
 ## 2.2.0
 
 ### Added

src/Result/ListQueuesResult.php

@@ -72,7 +72,7 @@ public function getQueueUrls(bool $currentPageOnly = false): iterable
         $page = $this;
         while (true) {
             $page->initialize();
-            if ($page->nextToken) {
+            if (null !== $page->nextToken) {
                 $input->setNextToken($page->nextToken);
 
                 $this->registerPrefetch($nextPage = $client->listQueues($input));