do not display threshold when vulnerability_count is none

Signed-off-by: tdruez <tdruez@aboutcode.org>

Author: tdruez

product_portfolio/templates/product_portfolio/compliance_dashboard.html

@@ -128,7 +128,7 @@ <h1 class="h3 mb-0">{% trans "Compliance Control Center" %}</h1>
               {% endif %}
             </td>
             <td class="text-end">
-              {% if product.risk_threshold %}
+              {% if product.risk_threshold and product.vulnerability_count %}
                 <span class="text-body-tertiary fs-xs" data-bs-toggle="tooltip" title="{% trans 'Risk threshold' %}">
                   &ge; {{ product.risk_threshold }}
                 </span>