/**
     * @Route("/register", name="app_register")
     */
    public function register(UserPasswordEncoderInterface $encoder): Response
    {
        $user = new User();
        $plainPassword = 'haslo';
        $encoded = $encoder->encodePassword($user, $plainPassword);
        
        $user->setEmail('email@email.com');
        $user->setRoles(['ROLE_ADMIN']);
        $user->setPassword($encoded);
        
        $entityManager = $this->getDoctrine()->getManager();
        $entityManager->persist($user);
        $entityManager->flush();
        
        return $this->redirectToRoute('admin_index');
    }