Remove the deprecated DeleteContainerRepositoryWorker

Context

In #217702 (closed) we decided to switch the background job to a limited capacity one for performance and stability reasons.

Problem to solve

The problem is that the old deprecated DeleteContainerRepositoryWorker has not been removed from the codebase.

Proposal

  • Remove the DeleteContainerRepositoryWorker class.
  • Adds a migration to remove any queued job instance.