pgsql: Fix up references to scram-sha-256

Fix up references to scram-sha-256

pg_hba_file_rules erroneously reported this as scram-sha256.  Fix that.

To avoid future errors and confusion, also adjust documentation links
and internal symbols to have a separator between "sha" and "256".

Reported-by: Christophe Courtois <christophe.courtois@dalibo.com>
Author: Michael Paquier <michael.paquier@gmail.com>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/38d485fdaa5739627b642303cc172acc1487b90a

Modified Files
--------------
doc/src/sgml/protocol.sgml           |  2 +-
src/backend/libpq/auth.c             | 16 ++++++++--------
src/backend/libpq/hba.c              |  2 +-
src/include/common/scram-common.h    |  4 ++--
src/interfaces/libpq/fe-auth-scram.c |  4 ++--
src/interfaces/libpq/fe-auth.c       |  8 ++++----
6 files changed, 18 insertions(+), 18 deletions(-)