pgsql: Doc: Fix incorrect mention to connection_object in CONNECT comma

Doc: Fix incorrect mention to connection_object in CONNECT command of ECPG

This fixes an inconsistency with this parameter name not listed in the
command synopsis, and connection_name is the parameter name more
commonly used in the docs for ECPG commands.

Reported-by: Yusuke Egashita
Discussion: /messages/by-id/156870956796.1259.11456186889345212399@wrigleys.postgresql.org
Backpatch-through: 9.4

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ae2d826922b745ea2c77c51019948ccf4309f50f

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