feat: update extended support description

Author: nijel

weblate_web/templates/support.html

@@ -93,6 +93,7 @@ <h2>{% translate "Extended self-hosted support" %}</h2>
               <li>{% translate "Issues in your environment fixed immediately." %}</li>
               <li>{% translate "Priority e-mail support." %}</li>
               <li>{% translate "Only available with the installation package" %}</li>
+              <li>{% translate "Be prepared with security notifications prior to the fix publication." %}</li>
             </ul>
             <a href="{% url 'subscription-new' %}?plan=extended"
                class="format-item bottom-left">{{ extended_support_package.price|price_format }}<span>{% translate "annually" %}</span></a>