Resolve "Introduce the `finalized` status (Update helpers)"

What does this MR do and why?

In this merge request, we are changing the logic of the ensure_batched_background_migration_is_finished helper. With this change, when a migration with ensure_batched_background_migration_is_finished is executed, the system moves the batched background migration to the state finalized if it finishes.

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Related to #441664