title: Is it possible to filter the user through roles (a JSON array) in EasyAdmin?
body: <p>I use <strong>EasyadminBundle</strong> for the Backend of a <strong>Symfony</strong> application.</p>
  
  <p>I'd like to filter my users through their <code>$roles</code> with 1 table with only the <code>ROLE_WEBMASTER</code>, another on with the <code>ROLE_ADMIN</code> and the final one with the loosers (<code>ROLE_USER</code>). </p>
  
  <p>Unfortunately the <code>$roles</code> member of the <code>User</code> class is an array.</p>
  
  <pre><code>class User implements UserInterface
  {
      /**
       * @ORM\Column(type="json")
       */
      private $roles = [];
  }
  </code></pre>
  
  <p>My storage back-end is SQLite.</p>
  
  <p>I tried two solutions: </p>
  
  <h2>1. use search queries</h2>
  
  <pre><code>- { icon: user-tie, label: admin, entity: User, params: {action: search, query: ROLE_ADMIN}}
  </code></pre>
  
  <blockquote>
    <p>do nothing</p>
  </blockquote>
  
  <h2>2. use a DQL filter</h2>
  
  <pre><code>webmaster:
      class: App\Entity\User
      label: Webmaster
      list:
          dql_filter: "'ROLE_WEBMASTER' IN entity.sqlRoles()"
  </code></pre>
  
  <p>with </p>
  
  <pre class="lang-php prettyprint-override"><code>public function  sqlRoles():string
  {
      return implode(', ',$this-&gt;getRoles());
  }
  </code></pre>
  
  <p>but it launch the following error </p>
  
  <blockquote>
    <p>An exception has been thrown during the rendering of a template ("[Syntax Error] line 0, col 65: Error: Expected =, &lt;, &lt;=, &lt;>, >, >=, !=, got 'IN'").  </p>
  </blockquote>
  
  <hr>
  
  <p>Is there a way to perform this kind of trick or do I need to forget this idea ?</p>