Bug 18434: Elasticsearch indexing broken with newer catmandu version

Bug 18434: Elasticsearch indexing broken with newer catmandu version

To test:
1 - Make sure you have latest koha deps, catmandu versions should be:
    libcatmandu-marc-perl   1.09-1~kohadev1
    libcatmandu-perl        1.0304-2~kohadev1
2 - Reindex elastic
3 - Try searching and likely notice odd results
4 - Try:
curl -XGET
'http://localhost:9200/koha_kohadev_biblios/data/792?pretty=true'
with a known biblionumber and notice some null fields
5 - Apply patch
6 - Reindex
7 - Note fields are populated and search works as expected

Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>