Hello,
This was changed in 8.3 when IPSec SA authentication for OSPF was introduced.
AFAIK, one cannot really use "regular" IPSec SA authentication for an OSPF area, "regular" IPSec (except GDOI) is point-to-point. To maintain consistency, OSPF authentication was moved under [edit protocols ospf area <id> interfaces].
HTH
Regards
Alex