Bug 24027: Call ModZebra once after all items added/deleted in a batch

Bug 24027: Call ModZebra once after all items added/deleted in a batch

Issue description:
- call to ModZebra was unconditional inside 'store' method for Koha::Item,
  so it was after each item added, or deleted.
- ModZebra called with param biblionumber, so it is the same parameter
  across calls for each items with same biblionumber, especially when we
  adding/removing in a batch.
- with ElasticSearch enabled this makes even more significant load
  and it is also progressively grows when more items already in DB

Solution:
- to add extra parameter 'skip_modzebra_update' and propagate it down to
 'store' method call to prevent call of ModZebra,
- but to call ModZebra once after the whole batch loop in the upper layer

Test plan / how to replicate:
- make sure that you have in the admin settings "SearchEngine" set to
  "Elasticsearch" and your ES is configured and working
  ( /cgi-bin/koha/admin/preferences.pl?op=search&searchfield=SearchEngine )
- select one of biblioitems without items
  ( /cgi-bin/koha/cataloguing/additem.pl?biblionumber=XXX )
- press button "add multiple copies of this item",
- enter 200 items, start measuring time and submit the page/form...

On my test machine when adding 200 items 3 times in a row (so 600 in
total, but to show that time grows with every next batch gradually):

WHEN ElasticSearch DISABLED (only Zebra queue):
- 9s, 12s, 13s
WHEN ElasticSearch ENABLED:
- 1.3m, 3.2m, 4.8m
WITH PATCH WHEN ElasticSearch ENABLED:
- 10s, 13s, 15s

Same slowness (because also same call to ModZebra) happens when you try
to delete all items ("op=delallitems"). And same fix.

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