Обсуждение: pgsql: Assorted fixes for jsonpath documentation

Assorted fixes for jsonpath documentation

This commit contains assorted fixes for jsonpath documentation including:
grammar fixes, incorrect examples fixes as well as wording improvements.

Discussion: https://postgr.es/m/CAA-aLv4VVX%3Db9RK5hkfPXJczqaiTdqO04teW9i0wiQVhdKcqzw%40mail.gmail.com
Author: Liudmila Mantrova
Reviewed-by: Alexander Korotkov
Reported-by: Thom Brown
Backpatch-through: 12

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a5c2f3a346fcda21d3dc9227b2c07854a7973729

Modified Files
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doc/src/sgml/func.sgml | 73 +++++++++++++++++++++++++++++---------------------
doc/src/sgml/json.sgml | 44 +++++++++++++++---------------
2 files changed, 64 insertions(+), 53 deletions(-)