Bug 10258: offer to create basket group only when staff user has correct permission

Bug 10258: offer to create basket group only when staff user has correct permission

If the staff user does not have the group_manage acquisition permission,
do not offer to create a new basket group when closing an order basket.

This avoids a situation where if a staff member without that permission tries
to close a basket and chose the option to create a bakset group, they would
be redirected to the login page.

To test:

[1] Log in as a staff user that does not have
    the acquisition/group_manage permission.
[2] Create a new order basket, attach at least one
    order line to it, then close it.
[3] Verify that the confirmation page does not
    offer to create a basket group with the
    same name as the order basket.
[4] Log in as a staff user that has the
    acquisition/group_manage permission.
[5] Create and close an order basket.
[6] Verify that this time, the confirmation page
    *does* offer to create a basket group.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>