DAL: remove refs to closed issues

To be done after the current issue triage.

List:

• #3103 (closed)
• #3605 (closed)
• #4084 (closed)
• #5415
• #7068 (closed)
• #5676 (closed); re-open?
• #3168 (closed) (easy task)
• #4289 (closed) (edit and re-open)
• #4458 (closed)
• #5143 (closed)