pgsql: doc PG 19 relnotes: add author and move items

doc PG 19 relnotes: add author and move items

Reported-by: Richard Guo

Author: Richard Guo

Discussion: /messages/by-id/CAMbWs4_etzZZPMEzte8hJv2f4Tn6dGskg8v1R_N9uCd2of0kMQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/191a037d4f2d0a028c19e9ca29da72bc79d2236e

Modified Files
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doc/src/sgml/release-19.sgml | 83 ++++++++++++++++++++++----------------------
1 file changed, 41 insertions(+), 42 deletions(-)