Following the recent reorganisation of the documentation in 12.0+, the
majority
of the documents have been moved and their old links are no longer
valid.
Some redirection rules will soon be deployed, but those rules might be
dropped in some
years and we want the links to still work, which is why we still replace
the links to the new ones.

FW-Port of odoo/odoo#70675 (13.0)

closes odoo/odoo#70726

Related: odoo/enterprise#18281
Signed-off-by: Victor Feyens (vfe) <vfe@odoo.com>