Fix retry mechanism for projects with pending_delete status

What does this MR do and why?

Projects with pending_delete: true were being excluded from the marked_for_deletion_before scope due to the without_deleted filter. This prevented the retry mechanism from working properly for projects that failed to complete the deletion process, leaving them stuck in a pending state.

References

https://gitlab.com/gitlab-com/request-for-help/-/issues/3859

Query plans

Ref: !216459 (merged)

How to set up and validate locally

1. Start the Rails console: rails console

2. Find a project and mark it as pending_delete:

   project = Project.last
   project.update!(
     marked_for_deletion_by_user_id: User.first.id,
     marked_for_deletion_at: 10.days.ago,
     pending_delete: true
   )

3. Verify the project is now included in the scope:

   Project.marked_for_deletion_before(Date.today).include?(project) # Expected: true (was false before the fix)

MR acceptance checklist

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Related to #583421