Обсуждение: pgsql: doc: move the mention of aggregate JSON functions up in section

doc:  move the mention of aggregate JSON functions up in section

It was previously easily overlooked at the end of several tables.

Reported-by: Alex Denman

Discussion: https://postgr.es/m/166335888474.659.16897487975376230364@wrigleys.postgresql.org

Backpatch-through: 10

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/5a495583a5b8aacb1b804ddcdf936e6d6c546050

Modified Files
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doc/src/sgml/func.sgml | 15 ++++++---------
1 file changed, 6 insertions(+), 9 deletions(-)