Fix document key usage in RerenderListener

Author: jaapio

packages/guides-cli/src/DevServer/RerenderListener.php

@@ -102,8 +102,8 @@ public function __invoke(FileModifiedEvent $event): void
 
         $this->commandBus->handle(
             new RenderDocumentCommand(
-                $this->documents[$file],
-                $renderContext->withDocument($this->documents[$file]),
+                $this->documents[$key],
+                $renderContext->withDocument($this->documents[$key]),
             ),
         );