Bug 26407: fix query in 'title exists' in `search_for_data_inconsistencies.pl`

Bug 26407: fix query in 'title exists' in `search_for_data_inconsistencies.pl`

Bug 23871 added check for 'title exists' to `search_for_data_inconsistencies.pl`.
There is a typo in DBIx query to create or : hashref instead of arrayref.

Test plan :
1) Change title of biblio record XXX in SQL :
   UPDATE biblio SET title = '' WHERE biblionumber=XXX
2) Change title of biblio record YYY in SQL :
   UPDATE biblio SET title = NULL WHERE biblionumber=YYY
3) Run misc/maintenance/search_for_data_inconsistencies.pl
4) Check you see both records

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>