pgsql: Doc: alphabetize aggregate function table

Doc: alphabetize aggregate function table

A few recent JSON aggregates have been added without much consideration
to the existing order.  Put these back in alphabetical order (with the
exception of the JSONB variant of each JSON aggregate).

Author: Wolfgang Walther <walther@technowledgy.de>
Reviewed-by: Marlene Reiterer <marlene.reiterer.03@gmail.com>
Discussion: https://postgr.es/m/6a7b910c-3feb-4006-b817-9b4759cb6bb6%40technowledgy.de
Backpatch-through: 16, where these aggregates were added

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/2645f6d643d929007fa7d1ed6d2de5155e4d63d8

Modified Files
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doc/src/sgml/func.sgml | 96 +++++++++++++++++++++++++-------------------------
1 file changed, 48 insertions(+), 48 deletions(-)