Merge !320: dnssec/nsec: add a precaution for DS nodata

5 jobs for master in 76 minutes and 34 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
canceled #72912
amd64 linux docker
build:linux:amd64

passed #19868
docker linux amd64
build:linux:amd64

00:00:42

 
  Test
passed #19870
docker linux amd64
deckard:linux:amd64

00:00:24

passed #19871
docker linux amd64 allowed to fail
respdiff:linux:amd64

01:16:34

passed #19869
docker linux amd64
test:linux:amd64

00:00:16