[ML] Bump version to 9.99.3

[elastic-vault-github-plugin-prod]

Automated patch version bump for branch 9.99.

elasticsearchVersion	9.99.2 → 9.99.3

When merging is enabled (VERSION_BUMP_NO_MERGE not true): auto-merge (gh pr merge --auto --squash) if VERSION_BUMP_MERGE_AUTO=true, otherwise immediate squash (gh pr merge --squash). Override merge style with VERSION_BUMP_MERGE_METHOD.

[prodsecmachine]

✅ Snyk checks have passed. No issues have been found so far.

Status	Scan Engine	Critical	High	Medium	Low	Total (0)
✅	Open Source Security	0	0	0	0	0 issues
✅	Licenses	0	0	0	0	0 issues

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