Update banner (#32)

Update banner to notify of url change

theme_overrides/main.html

@@ -6,5 +6,5 @@
 {% endblock %}
 
 {% block announce %}
-  <p class="announce">We want to know how you use GBFS, take the Annual Survey <a href="https://share.mobilitydata.org/annual-GBFS-survey" target="_blank">here</a>.  🚀 </p>
+  <p class="announce"> We are thrilled to announce that gbfs.mobilitydata.org is now gbfs.org 🚀 </p>
 {% endblock %}