pgsql: Schema-qualify unnest() in ALTER DATABASE ... RESET

Schema-qualify unnest() in ALTER DATABASE ... RESET

Commit 9df8727c5067 failed to schema-quality the unnest() call in the
query used to list the variables in ALTER DATABASE ... RESET. If there's
another unnest() function in the search_path, this could cause either
failures, or even security issues (when the tab-completion gets used by
privileged accounts).

Report and fix by Dagfinn Ilmari Mannsåker. Backpatch to 18, same as
9df8727c5067.

Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://postgr.es/m/87qzyghw2x.fsf%40wibble.ilmari.org
Discussion: https://postgr.es/m/87tt4lumqz.fsf%40wibble.ilmari.org
Backpatch-through: 18

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dbf5a83d4650fc893838a2f92306b3d6439f55ba

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