Move Slack API endpoints to Core

What does this MR do and why?

This change is part of #355896 (closed) to move all GitLab for Slack app code to Core.

This MR focuses on moving:

  • The integrations/slack/events and integrations/slack/interactions API endpoints
  • Related handling services and workers

A changelog entry, and any documentation changes, will be added in the final MR.

There should be no functional changes.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

Related to #355896 (closed)

Merge request reports

Loading