pgsql: Make libpq error messages consistent for translation

Make libpq error messages consistent for translation

The errormessage for an incorrect require_auth method wasn't using the
common "invalid %s value" errormessage which lessens the burden on our
translators.  Fix by changing to that format to make use of existing
translations and to make error messages consistent in wording.

Reported and fixed by Gurjeet Singh with some tweaking by myself.

Author: Gurjeet Singh <gurjeet@singh.im>
Discussion: https://postgr.es/m/CABwTF4Xu3g9zohJ9obu8m7MKbf8g63NgpRDjwqPHQgAtB+Gb8Q@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/60ce452729239f10ebbd0803a0ecc460f7f9238a

Modified Files
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src/interfaces/libpq/fe-connect.c         | 4 ++--
src/test/authentication/t/001_password.pl | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)