Fix code 4-FirstExtension/5-controlling-the-flow.rst

[MaStarzi]

I am not feeling confident with editing it myself through GitHub so I will just comment this here.

There is an error in the "Controlling the flow" page in the tutorial.
Inside the listAction() method the return is given a createHtmlResponse() which seems to not exist. So if you'd be recreating the Extension step-by-step you'd run into this error without knowing why.

public function listAction(): ResponseInterface
   {
      $products = $this->productRepository->findAll();
      $this->view->assign('products', $products);

      return $this->responseFactory->createHtmlResponse($this->view->render());
   }

The code used in the (working) extension "store_inventory" is:

public function listAction(): ResponseInterface
    {
        $products = $this->productRepository->findAll();
        $this->view->assign('products', $products);
        return $this->htmlResponse();
    }

This was probably overseen when the tutorial was updated.

[linawolf]

This example was removed as it was severely outdated in many places.

We are in process of removing the Extbase Fluid Book alltogether.