[FIX] project: incorrect creation of recurring tasks

In case X several recurrences are processed in the same cron execution,
only the last recurring task was created X times, while the other tasks
were not created. There is also a missing id preventing a correct use of
the default stage for the new created task.

closes odoo/odoo#70633

Signed-off-by: Yannick Tivisse (yti) <yti@odoo.com>