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

src/bin/psql/help.c

@@ -685,7 +685,7 @@ void
 print_copyright(void)
 {
 	puts("PostgreSQL Database Management System\n"
-		 "(formerly known as Postgres, then as Postgres95)\n\n"
+		 "(also known as Postgres, formerly known as Postgres95)\n\n"
 		 "Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group\n\n"
 		 "Portions Copyright (c) 1994, The Regents of the University of California\n\n"
 		 "Permission to use, copy, modify, and distribute this software and its\n"