Bug 28365: Add unit test

Bug 28365: Add unit test

Run prove t/db_dependent/Search.t

Without fix you get error :
    #   Failed test 'buildQuery should keep 0 value in query_cgi'
    #   at t/db_dependent/Search.t line 670.
    #          got: 'idx=su%2Cphr'
    #     expected: 'idx=su%2Cphr&q=0'

This patch also adds a test for query_desc in case it is broken in the
future.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>