ensure old XmlHttpRequest keep working

Author: samsonasik

spec/Middleware/MezzioSpec.php

@@ -364,7 +364,7 @@
                 );
 
                 $request  = $this->request;
-                $request  = $request->withHeader('X-Requested-With', 'XMLHttpRequest');
+                $request  = $request->withHeader('X-Requested-With', rand(0, 1) ? 'XMLHttpRequest' : 'XmlHttpRequest');
 
                 $handler  = Double::instance(['implements' => RequestHandlerInterface::class]);
                 allow($handler)->toReceive('handle')->with($request)->andRun(function (): never {