minor #11083 Update create_custom_field_type.rst (beamop)

This PR was merged into the 4.2 branch.

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Update create_custom_field_type.rst

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68e9bec Update create_custom_field_type.rst

Author: javiereguiluz

form/create_custom_field_type.rst

@@ -150,12 +150,12 @@ link for details), create a ``shipping_widget`` block to handle this:
         {% spaceless %}
             {% if expanded %}
                 <ul {{ block('widget_container_attributes') }}>
-                {% for child in form if not child.rendered %}
-                    <li>
-                        {{ form_widget(child) }}
-                        {{ form_label(child) }}
-                    </li>
-                {% endfor %}
+                  {% for child in form if not child.rendered %}
+                      <li>
+                          {{ form_widget(child) }}
+                          {{ form_label(child) }}
+                      </li>
+                  {% endfor %}
                 </ul>
             {% else %}
                 {# let the choice widget render the select tag #}