Update sonata_type_model_autocomplete.html.twig

Fix Bug with subclass inheritance and model_type_autocomplete

Resources/views/Form/Type/sonata_type_model_autocomplete.html.twig

@@ -64,6 +64,11 @@ file that was distributed with this source code.
                                 {% elseif admin_code %}
                                     'admin_code':  '{{ admin_code }}',
                                 {% endif %}
+                                
+                                 // subclass
+                                {% if app.request.query.get('subclass') %}
+                                    'subclass': '{{ app.request.query.get('subclass') }}',
+                                {% endif %}
 
                                 {% if context == 'filter' %}
                                     'field':  '{{ full_name|replace({'filter[': '', '][value]': '', '__':'.'}) }}',