Remove realtime indexing from TransferJob

[digitaldogsbody]

Purpose

The TransferJob used to move all DOIs from one client to another was causing errors because it couldn't find the ElasticSearch client for some reason, and was therefore getting stuck in a loop and repeatedly retrying the job, causing the queues and the workers to back up and get stuck in an infinite loop.

Since the DOI is updated (client_id/datacenter change) it triggers the indexable concern and goes onto the queue to be indexed anyway, and we previously decided that with our current better queue management and autoscaling that the real-time indexing is no longer critical (c.f #1147), the simple fix is just to remove the real-time indexing functionality from this job.

closes: Add github issue that originated this PR

Approach

Open Questions and Pre-Merge TODOs

Learning

Types of changes

• Bug fix (non-breaking change which fixes an issue)

• New feature (non-breaking change which adds functionality)

• Breaking change (fix or feature that would cause existing functionality to change)

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