Bug 24389: Better error handle when claiming late orders

Bug 24389: Better error handle when claiming late orders

A successful message says that the email has been sent and the order has
been claimed, but nothing happened.

Test plan:
0. Do not apply this patch
1. Create a new vendor, does not create a contact
2. Create some orders, close the basket
3. Go to the late orders page and claims some orders
=> You get a successful message, but the claim has not been done!
4. Apply this patch
5. Claim the orders
=> You get an error
6. Set a contact for the vendor
7. Claim the orders
=> Success

In the docker container, you may need to:
% apt install postfix
% postfix start
Edit /etc/hosts
127.0.0.1       localhost localhost.localdomain

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Joonas Kylmälä <joonas.kylmala@helsinki.fi>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>