Cleanup redundant headers from proxy.conf

Also general cleanup of whitespace

calibre.subdomain.conf.sample

@@ -35,7 +35,5 @@ server {
         proxy_pass $upstream_proto://$upstream_app:$upstream_port;
 
         proxy_buffering off;
-        proxy_set_header Upgrade $http_upgrade;
-        proxy_set_header Connection $http_connection;
     }
 }