Update u_e-80_to_443.md

docs/u_e-80_to_443.md

@@ -11,7 +11,7 @@ server {
   root /web;
   listen 80 default_server;
   listen [::]:80 default_server;
-  server_name _;
+  include /etc/nginx/conf.d/server_name.active;
   if ( $request_uri ~* "%0A|%0D" ) { return 403; }
   location ^~ /.well-known/acme-challenge/ {
     allow all;