style(router): include naxsi rules only once

Author: mboersma

router/image/templates/nginx.conf

@@ -36,7 +36,6 @@ http {
 
     {{ $useFirewall := or .deis_router_firewall_enabled "false" }}{{ if eq $useFirewall "true" }}# include naxsi rules
     include     /opt/nginx/firewall/naxsi_core.rules;
-    include     /opt/nginx/firewall/naxsi_core.rules;
     include     /opt/nginx/firewall/web_apps.rules;
     include     /opt/nginx/firewall/scanner.rules;
     include     /opt/nginx/firewall/web_server.rules;{{ end }}