nginx: Raise worker NOFILE limits

This is mostly to resolve issues on luna where nginx is hitting the
limit, but the higher limit won't hurt other machines so I'm not putting
it in a variable for now.
Signed-off-by: Florian Pritz <bluewind@xinu.at>

roles/nginx/templates/nginx.conf.j2

@@ -4,9 +4,11 @@ load_module /usr/lib/nginx/modules/ngx_http_brotli_filter_module.so;
 load_module /usr/lib/nginx/modules/ngx_http_brotli_static_module.so;
 
 events {
-    worker_connections  1024;
+    worker_connections  2048;
 }
 
+worker_rlimit_nofile 2048;
+
 error_log syslog:server=unix:/dev/log,nohostname info;
 
 http {