fix: usr: Log dropped or slipped responses in the query-errors category

Responses which were dropped or slipped because of RRL (Response Rate
Limiting) were logged in the ``rate-limit`` category instead of the
``query-errors`` category, as documented in ARM. This has been fixed.

Closes #5388

Merge branch '5388-rrl-log-category-fix' into 'main'

See merge request isc-projects/bind9!10676