Add IPv6 setting to nginx conf (#1582)

* Added IPv6 setting to nginx conf

https://matrix.to/#/!yomrOFwgFXzmeMAbzX:matrix.org/$sIkSxL002BKottY1Fop-bkusuyCJ1Y0zIFzqSWDYRrc?via=matrix.org&via=privacytools.io&via=dendrite.link

* Add IPv6 support to polylith nginx conf also

docs/nginx/monolith-sample.conf

@@ -1,5 +1,6 @@
 server {
-    listen 443 ssl;
+    listen 443 ssl; # IPv4
+    listen [::]:443; # IPv6
     server_name my.hostname.com;
 
     ssl_certificate /path/to/fullchain.pem;

docs/nginx/polylith-sample.conf

@@ -1,5 +1,6 @@
 server {
-    listen 443 ssl;
+    listen 443 ssl; # IPv4
+    listen [::]:443; # IPv6
     server_name my.hostname.com;
 
     ssl_certificate /path/to/fullchain.pem;