9.3.6: update versions

[elastic-observability-automation]

Merge on request by the Release Manager.

[github-actions]

🤖 GitHub comments

Just comment with:

• run docs-build : Re-trigger the docs validation. (use unformatted text in the comment!)

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 7910c58

[mergify]

This pull request is now in conflicts. Could you fix it @elastic-observability-automation[bot]? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b update-9.3.6 upstream/update-9.3.6
git merge upstream/9.3
git push upstream update-9.3.6