title: Using slug as a filter with Graphql and Strapi V4
body: <p>Trying to use slug as an uuid to fetch single pages from a strapi backend v4.
  my query to get pages works well. It's just I can't filter using slug:</p>
  <p>my pages query:</p>
  <pre class="lang-json prettyprint-override"><code>  query {
     pages {
      data {
        attributes {
              Name
              slug
        }
      }
   }
  }
  </code></pre>
  <p>how to get single page using <code>slug</code> uuid within this schema ? every trails to implement ($slug: String!) fails as where to locate slug.</p>