Обсуждение: pgsql: doc: PG 16 relnotes: move role INHERIT item and clarify it

doc:  PG 16 relnotes:  move role INHERIT item and clarify it

Also split out new role ADMIN syntax entry.

Reported-by: Pavel Luzanov

Discussion: https://postgr.es/m/0ebcc8ea-7f5a-d014-d53f-e078622be35d@aklaver.com

Backpatch-through: 16 only

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/00be0bc3d57f1b01249429bc0a154ecb41e02e7f

Modified Files
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doc/src/sgml/release-16.sgml | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)