Bug 22386: Define patron variable when matchign on extended attributes

Bug 22386: Define patron variable when matchign on extended attributes

For all other methods we define a patron object and check the userid,
we just need to define the $patron here

To test:
0 - Apply unit test patch alone
1 - prove t/db_dependent/Koha/Patrons/Import.t
2 - It dies
3 - Apply this patch
4 - repeat tests
5 - It passes!

Signed-off-by: Devlyn Courtier <dcourtier@hccc.edu>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>