logstash-elasticsearch-output docs are missing information about datastreams limitations

[mark54g]

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Description:

Certain available options like retry_on_conflict or doc_as_upsert are not available for datastreams, but not explicitly called out as having that limitation in the docs, and will throw an error if used on a datastream.

URL:
https://www.elastic.co/guide/en/logstash/current/plugins-outputs-elasticsearch.html

Anything else?