Bug 23382: (follow-up) Ensure closed day is inside charge window

Bug 23382: (follow-up) Ensure closed day is inside charge window

We're testing with an hourly loan of 96 hours to catch a closed day.
However, our closed day was hard coded to be a Wednesday so if you ran
the tests on a Friday the 96 hour loan would not catch a Wednesday.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>