[FIX] mrp: confirm production order at the end

This commit removes the action_confirm from the run_manufacture to do it
only after all the orderpoints have been processed.

In case a production, created in run_manufacture, triggers procurements
for one of its component. And those procurements have the same
parameters than another one still not run because after the manufacture
one in the queue. This new procurement will replenish its quantity plus
the other procurement's one.

That means too much quantity will be replenished.

closes odoo/odoo#76549

Signed-off-by: Arnold Moyaux <amoyaux@users.noreply.github.com>