Re: PG 16 draft release notes ready

In E.1.2. Migration to Version 16, probably need mention, some
privilege command cannot restore.
if new cluster bootstrap superuser name is not the same as old one. "GRANT
x TO y GRANTED BY no_bootstrap_superuser; " will have error.

---pg15 dump content.
CREATE ROLE jian;
ALTER ROLE jian WITH SUPERUSER INHERIT CREATEROLE CREATEDB LOGIN
REPLICATION BYPASSRLS;
CREATE ROLE regress_priv_user1;
ALTER ROLE regress_priv_user1 WITH NOSUPERUSER INHERIT NOCREATEROLE
NOCREATEDB LOGIN NOREPLICATION NOBYPASSRLS;
CREATE ROLE regress_priv_user2;
ALTER ROLE regress_priv_user2 WITH NOSUPERUSER INHERIT NOCREATEROLE
NOCREATEDB LOGIN NOREPLICATION NOBYPASSRLS;
CREATE ROLE su1;
ALTER ROLE su1 WITH SUPERUSER INHERIT CREATEROLE NOCREATEDB LOGIN
NOREPLICATION NOBYPASSRLS;
GRANT regress_priv_user1 TO regress_priv_user2 GRANTED BY su1;

-----------restore in pg16
\i /home/jian/Desktop/dumpall_schema.sql
2023-05-22 08:46:00.170 CST [456584] ERROR: permission denied to grant
privileges as role "su1"
2023-05-22 08:46:00.170 CST [456584] DETAIL: The grantor must have the
ADMIN option on role "regress_priv_user1".
2023-05-22 08:46:00.170 CST [456584] STATEMENT: GRANT regress_priv_user1
TO regress_priv_user2 GRANTED BY su1;
psql:/home/jian/Desktop/dumpall_schema.sql:32: ERROR: permission denied to
grant privileges as role "su1"
DETAIL: The grantor must have the ADMIN option on role
"regress_priv_user1".