Add default_server

Author: nemchik

root/defaults/nginx/site-confs/default.conf.sample

@@ -4,8 +4,8 @@ server {
     listen 80 default_server;
     listen [::]:80 default_server;
 
-    listen 443 ssl http2;
-    listen [::]:443 ssl http2;
+    listen 443 ssl http2 default_server;
+    listen [::]:443 ssl http2 default_server;
 
     server_name _;