Investigate if Elasticsearch X-Opaque-Id is causing problems with deduplicating warnings in the deprecation logs for Elasticsearch

In https://www.elastic.co/guide/en/elasticsearch/reference/7.17/api-conventions.html#x-opaque-id :

The X-Opaque-Id header accepts any arbitrary value. However, we recommend you limit these values to a finite set, such as an ID per client. Don’t generate a unique X-Opaque-Id header for every request. Too many unique X-Opaque-Id values can prevent Elasticsearch from deduplicating warnings in the deprecation logs.

In GitLab we set this to the randomly generated correlation ID which means that there will be many unique ids. This might be an issue but I'm not sure how much of a problem we actually would have with "deduplicating warnings in the deprecation logs".

This was added years ago in !35403 (merged) so I doubt it's causing much trouble but it might be worth investigating to see if this is costing us some performance.