pgsql: Fix small memory leak in psql's \bind command

Fix small memory leak in psql's \bind command

psql_scan_slash_option() returns a malloc()'d result through a
PQExpBuffer, and exec_command_bind() was doing an extra allocation of
this option for no effect.

Introduced in 5b66de3.

Author: Kyotaro Horiguchi
Reviewed-by: Corey Huinker
Discussion: /messages/by-id/20230221.115555.89096938631423206.horikyota.ntt@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8bf5af2ee6ea82a79817692de94347086da96b43

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