Doc: make an editorial pass over the v15 release notes.
Rearrange, reword, clarify, fix markup, etc etc.
Also include commit bd8ac900d.
Branch
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REL_15_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/2b14b5b5d9d5cf2f039a90a670abaf7b2f37bbe6
Modified Files
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doc/src/sgml/release-15.sgml | 1110 ++++++++++++++++++++++--------------------
1 file changed, 589 insertions(+), 521 deletions(-)