Bug 17716: (followup) Remove dep on existing data and tidy

Bug 17716: (followup) Remove dep on existing data and tidy

This patch removes the requirement for this tests for the DB to include
at least 10 borrowers to pass. Borrowers are now created on each run
using t::lib::TestBuilder and a loop.

Bonus: some tiny changes to tidy the file.

To test:
- Run:
  $ prove t/db_dependent/CourseReserves.t
SUCCESS => Tests pass with and without the patch.
- Sign off :-D

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>