Revert "Find zoekt index through replicas"

What does this MR do and why?

We discovered that !161212 (merged) causes SLO violations

undefined method `id' for nil:NilClass

            index_ids << replica.indices.max_by(&:free_storage_bytes).id

This MR reverts it.

Revert "Merge branch 'jm-zoekt-replica-index-retrieval' into 'master'"

This reverts merge request !161212 (merged)

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