pgsql: Fix and polish JSON_TABLE documentation

Fix and polish JSON_TABLE documentation

Correct the JSON_TABLE synopsis to place the ON ERROR clause after the
PLAN clause, matching the grammar (the previous order could not be
typed). Replace a dangling reference to json_path_specification with
path_expression, the term the synopsis actually defines. Mark up the
PLAN DEFAULT keywords with <literal> and fix a couple of wording issues.
Also list OUTER before INNER consistently, including in the parent/child
join description, where OUTER is the default.

Author: Thom Brown <thom(at)linux(dot)com>
Discussion: https://postgr.es/m/CAA-aLv5PGAFmAEpbhKQz8wppoOOTHfo-=LJb2sAB3974-9QtOw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4a82912bb2a2bc757142eca48f0fded1817a9a7c

Modified Files
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doc/src/sgml/func/func-json.sgml | 42 ++++++++++++++++++++--------------------
1 file changed, 21 insertions(+), 21 deletions(-)