[Backport 4.2.x] Set related children's thumbnail to default 4#8674

ianwallen merged 2 commits into4.2.xgeonetwork/core-geonetwork:4.2.xfrom

backport-8622-to-4.2.xgeonetwork/core-geonetwork:backport-8622-to-4.2.xCopy head branch name to clipboard