[FIX] administration/on-premise: Incorrect ports

In Odoo 18 and lower versions, update notifications are sent over HTTP,
not HTTPS:

Odoo 18: bbcafb7bb1/odoo/tools/config.py (L78)
Odoo 17: a7ccd81fb2/odoo/tools/config.py (L78)
Odoo 16: 6b5a839428/odoo/tools/config.py (L78)

The documentation has listed 443 as the main port since 2019:
https://github.com/odoo/documentation/pull/324 , but what it mentions
about the most recent version of Odoo using services.odoo.com wasn't
true until Odoo 18: https://github.com/odoo/odoo/pull/163202 . That PR
kept the HTTP usage and not HTTPS as was originally intended:
https://github.com/odoo/odoo/pull/30272 .

closes odoo/documentation#11407

X-original-commit: 4d079db7f8
Signed-off-by: Xavier Platteau (xpl) <xpl@odoo.com>

content/administration/on_premise.rst

@@ -61,8 +61,8 @@ To resolve the issue:
   your **network and firewall settings** allow the Odoo server to open outgoing connections
   towards:
 
-  - Odoo 18.0 and above: `services.odoo.com` on port `443` (or `80`)
-  - Odoo 17.0 and below: `services.openerp.com` on port `443` (or `80`)
+  - Odoo 18.0 and above: `services.odoo.com` on port `80`
+  - Odoo 17.0 and below: `services.openerp.com` on port `80`
 
   These ports must be kept open even after registering a database, as the update notification runs
   once a week.