correct render through rendertron (incorrect css loading)

docker/dev/nginx-development-proxy.conf

@@ -17,8 +17,8 @@ server {
       if ($http_user_agent ~ "Prerender") {
           set $prerender 0;
       }
-      # Dev only - allow to test request image when forcing the user agent.
-      if ($request_uri ~* "gif|png|jpg|pdf|svg|jpeg") {
+
+      if ($request_uri ~* "gif|png|jpg|pdf|svg|jpeg|css") {
         set $prerender 0;
       }