Thread: pgsql: doc: Update RFC URLs

doc: Update RFC URLs

Consistently use the IETF HTML links instead of a random mix of
different sites and formats.  This also fixes one broken link for JSON
documentation.

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ebd3c790122aafee0fbc3d0a4db95dc8c5f53730

Modified Files
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doc/src/sgml/json.sgml     | 2 +-
doc/src/sgml/libpq.sgml    | 2 +-
doc/src/sgml/pgcrypto.sgml | 6 +++---
3 files changed, 5 insertions(+), 5 deletions(-)