Remove option to override the BatchBackend to customize MassIndexer

Description

The backend used by the MassIndexer is now not different than the standard backend; there still is a BatchBackend concept, but this is currently just a forwarding component sending work to the real backend.

Environment

None

Assignee

Unassigned

Reporter

Sanne Grinovero

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Suitable for new contributors

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Pull Request

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Feedback Requested

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Components

Fix versions

Priority

Minor
Configure