Check the cache for the underscore prefix name with qminimisation

Underscore prefix name results are only cached if there wasn't a
referral from the parent servers when answering the query.  If we
have any record of a query succeeding for that name, including
NXDOMAIN, we can safely skip looking for a referral for the base
label.
Name Stage Failure
failed
clang-format Precheck
$ if test "$(git status --porcelain | grep -Ev '\?\?' | wc -l)" -gt "0"; then git status --short; exit 1; fi
M lib/dns/resolver.c
?? clang-format.patch
Uploading artifacts for failed job
Uploading artifacts...
clang-format.patch: found 1 matching files and directories

Uploading artifacts as "archive" to coordinator... 201 Created
id=2498116 responseStatus=201 Created token=KR_Vsucz
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1

failed
danger Precheck
 * branch            main       -> FETCH_HEAD



Failing the build, there is 1 fail.
Feedback: https://gitlab.isc.org/isc-projects/bind9/merge_requests/6267#note_284430

Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1