just don't bother with catch all server_name

docker/production/nginx/default.conf

@@ -1,6 +1,6 @@
 server {
   listen 80 default_server;
-  server_name _;
+  server_name zappyzep.xyz;
 
   # Using a variable here stops nginx from crashing if the dev container is restarted or becomes otherwise unavailable
   set $backend_upstream "http://api:3001";