[FIX] website_form: fix translation issue in saas

In a SaaS server, the _meta_data variable will be translated when the
HTTP worker is spawned and it will be translated into whichever language
is set on the DB that spawns said worker. This causes issues when other
DBs use this worker as the variable may be translated into a language that is
not present in that DB. To rectify this issue, we use lazy translate so
the translation lookup is executed at rendering.

opw-3385997

closes odoo/odoo#128601

Signed-off-by: Romain Derie (rde) <rde@odoo.com>