Migration to backfill correct_work_item_type_id in work items index

Background

With [Cells 1.0] Default Work Item Types: Ensure wor... (&15272 - closed) we need to make sure values from work_item_types.id are sequential values 1 - 9. This affects the issues table, as we currently have a foreign key issues.work_item_type_id that relies on these values.

The work items index indexes the work_item_type_id field and will need to adjust to accommodate ensuring work item type IDs are constant sequential 1-9 values.

Proposal

• Backfill the field correct_work_item_type_id in the work items. Use the Elastic::MigrationBackfillHelper
• Update specs as needed