pgsql: doc PG 19 relnotes: improve awkward or confusing wording

doc PG 19 relnotes: improve awkward or confusing wording

Reported-by: Álvaro Herrera

Discussion: /messages/by-id/aiQPgZtALNqj4npv@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/eb77a521996f6b7900dc0dfe6346f7e3c88455bb

Modified Files
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doc/src/sgml/release-19.sgml | 29 ++++++++++++++++-------------
1 file changed, 16 insertions(+), 13 deletions(-)