pgsql: Last-minute updates for release notes.

Last-minute updates for release notes.

Security: CVE-2025-8713, CVE-2025-8714, CVE-2025-8715

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/2e19ad79e1a14e5dacd0ad3a3ec959fff928ca17

Modified Files
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doc/src/sgml/release-14.sgml | 129 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 128 insertions(+), 1 deletion(-)