Bug 14197: Remove the warning on destroying TestBuilder objects

Bug 14197: Remove the warning on destroying TestBuilder objects

This module will be called by db_dependent tests, which already create a
transaction.
TestBuilder creates a new one (which is certainly useless) and the
rollback does not do anything.

To see the warning see patches on bug 14045.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>