To match the defaults we set in Hibernate Search itself.
We have bumped the defaults in Search 8.0: https://hibernate.atlassian.net/browse/HSEARCH-5045
However, it appears that we never applied them to Quarkus. So this PR is to address that.
cc: @yrodiere
and a migration note could be:
== Hibernate Search

[[hibernate-search-client-defaults]]
=== Hibernate Search Elasticsearch client's defaults

Quarkus changes the defaults for the following Elasticsearch client configuration properties:

• `quarkus.hibernate-search-[orm|standalone].elasticsearch.max-connections` will be `40` by default, instead of `20`
• `quarkus.hibernate-search-[orm|standalone].elasticsearch.max-connections-per-route` will be `20` by default, instead of `10`

This is done to match the change in Hibernate Search itself that aims to prevent a potential consumption of
all connections by the indexing queues, leaving no available connections for search requests.

To keep the previous default Elasticsearch configuration, set the following configuration properties
(pick either `orm` or `standalone` variant depending on the Hibernate Search extension used):

[source,properties]

quarkus.hibernate-search-[orm|standalone].elasticsearch.max-connections=20
quarkus.hibernate-search-[orm|standalone].elasticsearch.max-connections-per-route=10