pgsql: Track behavior of \1 in pg_ident.conf when quoted

Track behavior of \1 in pg_ident.conf when quoted

Entries of pg-user in pg_ident.conf that are quoted and include '\1'
allow a replacement from a subexpression in a system user regexp. This
commit adds a test to track this behavior and a note in the
documentation, as it could be affected by the use of an AuthToken for
the pg-user in the IdentLines parsed.

This subject has come up in the discussion aimed at extending the
support of pg-user in ident entries for more patterns.

Author: Jelte Fennema
Discussion: https://postgr.es/m/CAGECzQRNow4MwkBjgPxywXdJU_K3a9+Pm78JB7De3yQwwkTDew@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0b717432ff13683f9d13f007dab1c3380cae2f0d

Modified Files
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doc/src/sgml/client-auth.sgml | 3 +++
src/test/authentication/t/003_peer.pl | 13 +++++++++++++
2 files changed, 16 insertions(+)