[AUTO] Add release notes for 2.19.5

[opensearch-ci-bot]

Add release notes for 2.19.5

[github-actions]

PR Reviewer Guide 🔍

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🧪 No relevant tests

🔒 No security concerns identified

✅ No TODO sections

🔀 No multiple PR themes

⚡ Recommended focus areas for review Misclassified Entry The entry "Fix SearchPhaseExecutionException to properly initCause" is listed under "Enhancements" but appears to be a bug fix based on its description. It should likely be under "Bug Fixes" instead. * Fix SearchPhaseExecutionException to properly initCause ([#20320](https://github.com/opensearch-project/OpenSearch/pull/20320))

[github-actions]

PR Code Suggestions ✨

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Category	Suggestion	Impact
General	Correct misclassified bug fix entry This entry is categorized under "Enhancements" but describes a fix, which should belong under "Bug Fixes". Misclassifying bug fixes as enhancements can mislead users about the nature of changes in the release. release-notes/opensearch.release-notes-2.19.5.md [11] +Move this entry to the "Bug Fixes" section: * Fix SearchPhaseExecutionException to properly initCause ([#20320](https://github.com/opensearch-project/OpenSearch/pull/20320)) Suggestion importance[1-10]: 5 __ Why: The entry "Fix SearchPhaseExecutionException to properly initCause" is indeed a bug fix based on its name, but it's listed under "Enhancements". This is a valid categorization concern that could mislead users about the nature of the change.	Low
	Add missing trailing newline to file The file is missing a newline at the end, which is a common requirement for text files and can cause issues with some tools and diff viewers. Add a trailing newline after the last line. release-notes/opensearch.release-notes-2.19.5.md [26] +* Bump log4j from 2.21.0 to 2.25.3 ([#20308](https://github.com/opensearch-project/OpenSearch/pull/20308)) - Suggestion importance[1-10]: 2 __ Why: The existing_code and improved_code are identical, making this suggestion unclear about what actual change needs to be made. While trailing newlines are a valid concern, the suggestion doesn't demonstrate the fix properly.	Low