fix: Skip block if urls not on phishtank.

website/web/templates/modules.html

@@ -28,12 +28,14 @@
 <center>
   <h1 class="display-4">Phishtank</h1>
   <div>
+    {% if phishtank.get('urls') %}
     <p>Phishtank flagged the URLs below as phishing:</p>
     <ul>
     {% for url, permaurl in phishtank['urls'].items() %}
       <li>{{ shorten_string(url, 150) }}: <a href="{{ permaurl }}">click to view it</a> on phishtank.</p></li>
     {% endfor %}
     </ul>
+    {% endif%}
 
     {% if phishtank.get('ips_hits') %}
     <p>The IPs below are in the tree and are flagged as phishing on Phishtank, might on on other URLs:</p>