[FIX] website: let the 404 exception catch by _handleException
[FIX] website: let the 404 exception catch by _handleException

Don't rewrite the wheel with serve_404.
It is the job of HandleException to do it.

In the same time, that will fix the status code that was
previously 200 instead of 404 in serve_404

This commit closes #22438

ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo