title: How can I change error message in Symfony
body: <p>I create a form and then when I click on submit button, show this error message:</p>
  
  <blockquote>
    <p>Please select an item in the list.</p>
  </blockquote>
  
  <p>How can I change this message and style it ( with CSS )?</p>
  
  <p>Entity:</p>
  
  <pre><code>...
      /**
       * @ORM\Column(type="string", length=255)
       * @Assert\NotBlank(message="Hi user, Please select an item")
       */
      private $name;
  ...
  </code></pre>
  
  <p>Controller:</p>
  
  <pre><code>...
          public function index(Request $request)
          {
              $form = $this-&gt;createForm(MagListType::class);
              $form-&gt;handleRequest($request);
              return $this-&gt;render('index.html.twig', [
                  'form' =&gt; $form-&gt;createView()
              ]);
          }
  ...
  </code></pre>
  
  <p>Form:</p>
  
  <pre><code>...
      public function buildForm(FormBuilderInterface $builder, array $options)
      {
          $builder
              -&gt;add('name', EntityType::class,[
                  'class' =&gt; InsCompareList::class,
                  'label' =&gt; false,
                  'query_builder' =&gt; function(EntityRepository $rp){
                  return $rp-&gt;createQueryBuilder('u')
                      -&gt;orderBy('u.id', 'ASC');
                  },
                  'choice_label' =&gt; 'name',
                  'choice_value' =&gt; 'id',
                  'required' =&gt; true,
              ])
              -&gt;add('submit', SubmitType::class, [
                  'label' =&gt; 'OK'
              ])
          ;
  ...
  }
  </code></pre>