Do not keep stale NXDOMAIN answers in cache

Related to #1283 (closed). Related to #1831.

From the discussion at 2022 All-hands Create new issue to not keep stale NXDOMAIN in cache.

Edited Jun 01, 2022 by Matthijs Mekking

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information