HitsMetadata total hits is mandatory, but shouldn't be.

[ls-urs-keller]

opensearch-java/java-client/src/main/java/org/opensearch/client/opensearch/core/search/HitsMetadata.java

Line 73 in e050cb0

this.total = ApiTypeHelper.requireNonNull(builder.total, this, "total");

E.g. when creating a NativeQuery using the query builder such as

NativeQuery.builder()
   ...
   .withTrackTotalHits(false)
   .build()

This results in org.opensearch.client.util.MissingRequiredPropertyException: Missing required property 'HitsMetadata.total'
Not tracking the totals is completely valid and can result in better performance when scrolling through the data (e.g. searchafter).

[dblock]

Is this a bug in the client or a feature request in the server? Either way maybe you can write a small unit test for this and PR a fix?