Move notifications from eboutic checkout to billing info fragment

eboutic/templates/eboutic/eboutic_billing_info.jinja

@@ -31,4 +31,5 @@
   </div>
 
   <br>
+  {% include "core/base/notifications.jinja" %}
 </div>

eboutic/templates/eboutic/eboutic_checkout.jinja

@@ -1,5 +1,9 @@
 {% extends "core/base.jinja" %}
 
+{% block notifications %}
+  {# Notifications are moved inside the billing info fragment #}
+{% endblock %}
+
 {% block title %}
   {% trans %}Basket state{% endtrans %}
 {% endblock %}