Remove AggregateRelationId from recordExtObjInitPriv()
This was erroneous, because AggregateRelationId has no OID, so it
cannot be part of an extension directly. (Aggregates are registered
via pg_proc.) No harm in practice, but better to make it correct.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/
504bc485-6bd6-dd1b-fe10-
e7351aeb310d@enterprisedb.com