The ingest `set` processor ([type SetProcessor](https://github.com/elastic/elasticsearch-specification/blob/025d85d754f8e91a9bdc2409631a66f87340096f/specification/ingest/_types/Processors.ts#L305)) is missing a lot of fields [described in the docs](https://www.elastic.co/guide/en/elasticsearch/reference/current/set-processor.html). Reported in [this Discuss topic](https://discuss.elastic.co/t/how-to-automatically-set-the-server-date-time-when-adding-data/296708/10) related to using `copy_to` in the Java Client