doc: Update RFC URLs
Consistently use the IETF HTML links instead of a random mix of
different sites and formats. Correct one RFC number and fix one broken
link.
Branch
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REL_10_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/ca49d69b7c8f04c495ce39ff4460e017656db901
Modified Files
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doc/src/sgml/client-auth.sgml | 2 +-
doc/src/sgml/json.sgml | 2 +-
doc/src/sgml/libpq.sgml | 2 +-
doc/src/sgml/pgcrypto.sgml | 6 +++---
4 files changed, 6 insertions(+), 6 deletions(-)