Bug 24567: (QA follow-up) Remove warning in regex

Bug 24567: (QA follow-up) Remove warning in regex

Without this patch we get

Use of uninitialized value $3 in concatenation (.) or string at /kohadevbox/koha/Koha/SearchEngine/Elasticsearch/QueryBuilder.pm line 943.

This converts the | OR operator to two different regexes so that the
capture group variables will be defined in every case.

Signed-off-by: Joonas Kylmälä <joonas.kylmala@helsinki.fi>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
(cherry picked from commit ea7e83b2712c48a0c9a157b2fb36eb782b26f34b)

Signed-off-by: Andrew Fuerste-Henry <andrew@bywatersolutions.com>