[FIX] auth_signup: add missing dependency on the  computation of the signup validity
[FIX] auth_signup: add missing dependency on the  computation of the signup validity

The field signup_valid is a non stored computed field based on signup_token.
The cache is filled with prefetched values, so in a loop the field is read from
the cache and not recomputed due to the missing dependency.

opw 1843442

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