Обсуждение: pgsql: Doc: update 11.4 release notes through today.

Doc: update 11.4 release notes through today.

Also improve wording of some items (thanks to Noah Misch for suggestions).

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f5ee6a7acc5db0d77f73aa1db531a684179b5478

Modified Files
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doc/src/sgml/release-11.sgml | 45 ++++++++++++++++++++++++++++++++++++--------
1 file changed, 37 insertions(+), 8 deletions(-)