Bug 25611: Use selected vendor when creating a basket

Bug 25611: Use selected vendor when creating a basket

We did not take into account the vendor selected.

Test plan:
1. Choose Vendor
2. Create Basket
3. Assign a new vendor
Without the patch this new vendor is not changed
With the patch applied the vendor is changed

4. Edit the basket, change the vendor

Reported-by: Kelly McElligott <kelly@bywatersolutions.com>
Signed-off-by: Rhonda Kuiper <rkuiper@roundrocktexas.gov>
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>