pgsql: Fix markup in synopsis

Fix markup in synopsis

There is no need for a <literal> inside a <synopsis>, since the latter
is already all "literal" implicitly. Also, create_help.pl misparses
it. So just remove it.

Reported-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: /messages/by-id/20220517.174342.1884842412165214815.horikyota.ntt@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/81e3c83d988daa8fd763ec5104d540713832dd1a

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