Bug 23971: (follow-up) Remove stale param

Bug 23971: (follow-up) Remove stale param

As highlighted by Jonathan in comment #90, we were passing
borrowernumber to ModBasket. This was a hangover from when we explicitly
logged the borrower, which was later discovered to be unnecessary
duplication, and was removed in commit "Remove data duplication".

This commit removes this unnecessary parameter.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>