[CHANGE] Only show username when there is a username

allianceauth/services/templates/services/services_ctrl.html

@@ -14,7 +14,9 @@
 {% endblock %}
 
 {% block user %}
+    {% if username %}
         Username: <span class="badge bg-secondary">{{ username }}</span>
+    {% endif %}
 {% endblock %}
 
 {% block controls %}