pgsql: doc: Add note about "Client User" and "Superuser" fields in \con

doc: Add note about "Client User" and "Superuser" fields in \conninfo output.

In the \conninfo psql command, the "Client User" column shows the user who
established the connection, while the "Superuser" column reflects whether
the current user in the current execution context is a superuser. This means
the users referred to in these columns can differ, for example, if the current
user was changed with the SET ROLE command.

This commit adds a note to the \conninfo documentation to clarify
this behavior and avoid potential confusion.

Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/685961b8-b6ce-40bb-b2d5-c2ff135d3388@oss.nttdata.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0fe50417eca46d6993da350845dc09d7e899c6d6

Modified Files
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doc/src/sgml/ref/psql-ref.sgml | 9 +++++++++
1 file changed, 9 insertions(+)