Bug 32250: Only reindex records when commiting

Bug 32250: Only reindex records when commiting

This patch adds an array to catch updated bibs, and defers indexing until a
batch of changes is committed

To test:
1 - Set LinkerModule system preference to either first or last match
    Alternate this between runs of the linker to ensure changes are made
2 - Set SearchEngine to Elasticsearch and reindex (to ensure index is built)
3 - perl  misc/link_bibs_to_authorities.pl -v
4 - Check Admin->Jobs and see that many ES index jobs are queued
5 - Apply patch
6 - perl  misc/link_bibs_to_authorities.pl -v
7 - Check Admin->Jobs and see that 1 index per commit from is enqueued

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