[Nginx] Enable TLSv1.3

data/conf/nginx/site.conf

@@ -14,7 +14,7 @@ server {
 
   ssl_certificate /etc/ssl/mail/cert.pem;
   ssl_certificate_key /etc/ssl/mail/key.pem;
-  ssl_protocols TLSv1.2;
+  ssl_protocols TLSv1.2 TLSv1.3;
   ssl_ciphers 'ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256';
   ssl_prefer_server_ciphers on;
   ssl_session_cache shared:SSL:50m;