pgsql: doc: Fix incorrect openssl option

doc: Fix incorrect openssl option

The openssl command for displaying the DN of a client certificate was
using --subject and not the single-dash option -subject. While recent
versions of openssl handles double dash options, earlier does not so
fix by using just -subject (which is per the openssl documentation).

Backpatch to v14 where this was introduced.

Reported-by: konkove@gmail.com
Discussion: /messages/by-id/170672168899.666.10442618407194498217@wrigleys.postgresql.org
Backpatch-through: v14

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/da9cb249575229cbdebd27a3ba398efd072aa84b

Modified Files
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doc/src/sgml/client-auth.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)