pgsql: Fix use of term "verifier"

Fix use of term "verifier"

Within the context of SCRAM, "verifier" has a specific meaning in the
protocol, per RFCs. The existing code used "verifier" differently, to
mean whatever is or would be stored in pg_auth.rolpassword.

Fix this by using the term "secret" for this, following RFC 5803.

Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Discussion: https://www.postgresql.org/message-id/flat/be397b06-6e4b-ba71-c7fb-54cae84a7e18%402ndquadrant.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b4675a8ae2d0aaafeb136c46c92bb56eaf018d32

Modified Files
--------------
src/backend/libpq/auth-scram.c | 104 +++++++++++++++---------------
src/backend/libpq/auth.c | 2 +-
src/backend/libpq/crypt.c | 8 +--
src/common/scram-common.c | 4 +-
src/include/common/scram-common.h | 6 +-
src/include/libpq/crypt.h | 2 +-
src/include/libpq/scram.h | 8 +--
src/interfaces/libpq/fe-auth-scram.c | 6 +-
src/interfaces/libpq/fe-auth.c | 2 +-
src/interfaces/libpq/fe-auth.h | 2 +-
src/test/authentication/t/001_password.pl | 2 +-
src/test/regress/expected/password.out | 12 ++--
src/test/regress/sql/password.sql | 12 ++--
13 files changed, 85 insertions(+), 85 deletions(-)