[FIX] mrp: Wrong replenishment order notification

On the commit 69dcdd41, the order='create_date desc'
 was removed and the way of getting the MO for the notification changed. Now, the context is used, it should be written_after instead of written_date.
In addition, the now declaration should be at the beginning of the method action_replenish.
(The MO created is correct, only the notification is wrong)

Should be forwarded
OPW-2877457

closes odoo/odoo#96085

Signed-off-by: William Henrotin (whe) <whe@odoo.com>