pgsql: doc: Mention PASSING support for jsonpath variables

doc: Mention PASSING support for jsonpath variables

Commit dfd79e2d added a TODO comment to update this paragraph
when support for PASSING was added. Commit 6185c9737cf added
PASSING but missed resolving this TODO. Fix by expanding the
paragraph with a reference to PASSING.

Author: Aditya Gollamudi <adigollamudi@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: /messages/by-id/20260117051406.sx6pss4ryirn2x4v@pgs

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/aa082bed0b6433b58815683dde425bce57ed931c

Modified Files
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doc/src/sgml/json.sgml | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)