[Backport 2.19-dev] Error handling for dot-containing field names

[opensearch-trigger-bot]

Backport 8126367 from #4907.

[coderabbitai]

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✨ Finishing touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch backport/backport-4907-to-2.19-dev

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