pgsql: psql: Fix note on project naming in output of \copyright.

psql: Fix note on project naming in output of \copyright.

This adjusts the wording to match the changes in commits
5987553fde, a233a603ba, and pgweb commit 2d764dbc08.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/aHVo791guQR6uqwT%40nathan
Backpatch-through: 13

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/149e6e7092e905a54010082d61307e6e9d397764

Modified Files
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src/bin/psql/help.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)