Bug 15082: t/db_dependent/Search.t shouldn't mock the DB connection

Bug 15082: t/db_dependent/Search.t shouldn't mock the DB connection

This patch makes the t/db_dependent/Search.t tests use a real DB instead of
mocking the DB handler (which is not actually used and generates unnecesary
warnings when running the tests).

It does so by grabbing the DB configuration data using C4::Context->config()
and passing it (writing %ENV) to rewrite-config.PL, all is done in zebra_config.pl
which is only used on the Search.t file.

To test:
- Run
  $ prove t/db_dependent/Search.t
=> FAIL: Warnings are raised about DB being mocked and DBIC not recognising 'Mock'
         as a valid DB driver.
- Apply the patch
- Run
  $ prove r/db_dependent/Search.t
=> SUCCESS: Same tests results, no warning about DBIC driver.
- Sign off :-D

Disclamer: As of writing this patch, the Search.t tests pass. The patch is not dealing
with tests results, but how they use the DB.

Sponsored-by: Universidad Nacional de Cordoba
Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Test pass before & after, a 'little' less noisy
No errors

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>