Bug 20180: [sql_modes] Remove GROUP BY clause in manage-marc-import.pl

Bug 20180: [sql_modes] Remove GROUP BY clause in manage-marc-import.pl

Replaced with a distinct.

Fix for:
'koha_kohadev.me.frameworktext' isn't in GROUP BY

t/db_dependent/www/search_utf8.t

NOTE: I added a [% frameworks.count %] into the template file,
      and compared master and a branch with this applied when
      managing a staged marc import. Values were identical.

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>