Обсуждение: pgsql: relnotes: updates "cumulative statistics system" mention

relnotes:  updates "cumulative statistics system" mention

Also add "the".

Reported-by: Justin Pryzby

Discussion: https://postgr.es/m/20220711173923.GV13040@telsasoft.com

Backpatch-through: 15 only

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d8759a40bfce756f655b2afab129915640bebf0a

Modified Files
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doc/src/sgml/release-15.sgml | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)