Backport 16.3 Fix cluster service reindexing params

What does this MR do and why?

Backport to %16.3 for !130107 (merged)

The zero downtime reindex feature is not functional, so we would like to backport the fix one release.

Note: documentation about the issue was added in !130234 (merged)

MR acceptance checklist

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• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
• The original MR has been deployed to GitLab.com (not applicable for documentation or spec changes).
• This MR has a severity label assigned (if applicable).
• This MR has been approved by a maintainer (only one approval is required).
• Ensure the e2e:package-and-test-ee job has either succeeded or been approved by a Software Engineer in Test.

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