fix(Zendesk) - organize ticket and article internal IDs per brand

[aubin-tchoi]

Description

• Close [Zendesk] Add the brandId in the internal IDs for tickets and articles #9691
• Close #1870
• Update all the methods that fetch Zendesk tickets, articles or categories by ID to also filter on the brand ID.
• Add the corresponding indexes.
• Change the internal ID for single tickets and articles to include the brand ID.
  • No migration required in front: single tickets and articles are never passed as parents.
  • Migration required in core: going to backfill new documents with the new ID (see deploy plan).

Risk

• Moderate risk of breaking the search on Zendesk data sources, relies on a carefully executed migration plan.

Deploy Plan

• Run the backfill.
• Run the migration that adds the indexes.
• Stop all Zendesk connectors.
• Deploy connectors.
• Resume all Zendesk connectors.
• Run the cleanup script.

[aubin-tchoi]

gonna do it in a different way, gonna cherry pick from this but won't merge