Release notes for 8.19.15

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[donoghuc]

@copilot draft the release notes. Look at the patterns in the file and make sure to follow them. The release notes for the commits i want are:

• e596c34 - DeadLetterQueueUtils#extractSegmentId improvement: replace split with index of and substring methods. (DeadLetterQueueUtils#extractSegmentId improvement: replace split with index of and substring methods. #18874) ([8.19] (backport #18874) DeadLetterQueueUtils#extractSegmentId improvement: replace split with index of and substring methods. #18958) (2 weeks ago) <mergify[bot]>
• 24786dd - Upgrade Log4j to 2.25.3 (Manual backport of Upgrade Log4j to 2.25.3 #18522) (Upgrade Log4j to 2.25.3 (Manual backport of #18522) #18943) (2 weeks ago)

Also, please fix the 404 for:

Elastic_integration Filter - 8.19.4

404: Not Found

[Copilot]

@copilot draft the release notes. Look at the patterns in the file and make sure to follow them. The release notes for the commits i want are:

• e596c34 - DeadLetterQueueUtils#extractSegmentId impr...

Added a "Performance improvements" section to the 8.19.15 release notes with an entry for the DeadLetterQueueUtils#extractSegmentId improvement (commit 0fc5bc1):

==== Performance improvements

* Improved performance of `DeadLetterQueueUtils#extractSegmentId` by replacing `split` with `indexOf` and `substring` methods https://github.com/elastic/logstash/pull/18874[#18874]

[yaauie]

While this is what had to be done in order to use the latest 8.19, this plugin release was about re-syncing with Elasticsearch 8.19 branch.

@mashhur do we have clarity about what version of Elasticsearch specifically is embedded in this plugin?

[mashhurs]

It was just before 8.19.14 release, we can say pre 8.19.14 sync up and on this day we had a BC.
What do you think if we either abstract:

• Sync up with Elasticsearch 8.19 branch to consume required modules
• or be more specific by adding ".. required modules from 8.19.14"
  ?

[mashhurs]

LGTM!