Bug 21811: Add JS confirmation when receiving - at least 1 item to receive

Bug 21811: Add JS confirmation when receiving - at least 1 item to receive

When receiving, the "receive items" form should not be submitted if no
items are going to be received

Test plan:
Create an order, close the basket, receive some items
On the "receive items" form, do not select item (if items are created
when placing the order) and submit the form
=> You must get a JS alert that prevent the form to be submitted
Select at least one item, submit again
=> Now it's submitted

Signed-off-by: Séverine QUEUNE <severine.queune@bulac.fr>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>