Bug 12416: add new tests of DelUniqueDebarment

Bug 12416: add new tests of DelUniqueDebarment

The subroutine DelUniqueDebarment was not enough tested

To test: execute the command prove t/db_dependent/Borrower_Debarments.t
The command has to print:
t/db_dependent/Borrower_Debarments.t .. ok
All tests successful.
Files=1, Tests=31,  1 wallclock secs ( 0.03 usr  0.01 sys +  1.44 cusr  0.08 csys =  1.56 CPU)
Result: PASS

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
All 31 test pass, no koha-qa errors

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
All tests pass.

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>