[IMP] mail: use _message_log_batch in create
[IMP] mail: use _message_log_batch in create

For 1000 records, these specific lines take:

- 2.1s before the commit
- 1.2s after the commit

Almost 2 times faster.

PR: #36654
Part of task-2070602
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo