Add event to events page (#407)

Author: RichardLitt

_data/events.yml

@@ -1,16 +1,22 @@
+- title: AI, FLOSS, and Sustainability Virtual Forum
+  location: Online
+  date: June 11, 2026
+  url: https://sustainoss.org/events/ai-floss-sustainability-forum-2026/
+  ranking: 1
+
 - title: Sustain Africa 2023
   location: Lagos, Nigeria
   date: June 15-17, 2023
   logo: sustain-africa-2023.svg
   url: https://blog.oscafrica.org/sustain-africa-2023-community-report
-  ranking: 1
+  ranking: 2
 
 - title: Sustain Africa 2022
   location: Lagos, Nigeria
   date: Mar 24-26, 2022
   logo: sustain-africa-2022.svg
   url: https://blog.oscafrica.org/sustain-africa-2022-community-report
-  ranking: 2
+  ranking: 3
 
 - title: Sustain Summit 2020
   location: Brussels, Belgium

events.html

@@ -26,7 +26,7 @@ <h1 class="h2 text-center mb-4 past-title">Past Events</h1>
     {% assign loopindex = forloop.index | modulo: 3 %}
       <div class="col-sm-6 col-md-4 event-container">
         {% if event.url %}<a href="{{ event.url }}">{% endif %}
-          <img src="/assets/img/events/{{ event.logo }}" alt="{{ event.title }}" class="card-image">
+        {% if event.logo %}  <img src="/assets/img/events/{{ event.logo }}" alt="{{ event.title }}" class="card-image">{% endif %}
         {% if event.url %}</a>{% endif %}
         <h4>{{ event.title }}</h4>
         <p class="details">