Bug 15159: TestBuilder behaviour on AI values should be tested

Bug 15159: TestBuilder behaviour on AI values should be tested

This patch introduces a test for t::lib::TestBuilder to check it
doesn't mess with AI values. As it is generating random values based
on the defined column type, chances are that it is creating the
AI values on its own, instead of letting the DB handle it.

This could be problematic of course. This test uses the 'biblio' table
by creating two values and checking their biblionumbers are consecutive.

To test:
- Apply the patch
- Run:
  $ prove t/db_dependent/TestBuilder.t -v
=> SUCCESS: The new tests are run and:
   - biblio.biblionumber is detected as an auto-increment column
   - generated biblionumbers are consecutive
- Sign off

Regards

Signed-off-by: Hector Castro <hector.hecaxmmx@gmail.com>
All tests successful.

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>