Add bulk_import_entity_id information to all Direct Transfer workers

On Kibana, it's a challenge to filter workers for a specific migration because the logs of the worker executions don't contain a property we can use to filter them.

Adding the meta attribute bulk_import_entity_id to the worker logs would allow us to visualize all the worker logs related to a specific migration.

Proposed solution

Add the meta attribute bulk_import_entity_id to the log that is generated when the worker starts and finishes