As far as i can tell amber is lacking these security updates due to downstream changes in popstgresql-common:
https://lists.debian.org/debian-security-announce/2019/msg00220.html
See https://master.pureos.net/synchrotron/
postgresql-common buster/updates amber-security 200+deb10u3 200pureos1 Requires manual merge of downstream changes with source.