pgsql: Drop the temporary tuple slots allocated by pgoutput.

Drop the temporary tuple slots allocated by pgoutput.

In pgoutput, when converting the child table's tuple format to match the
parent table's, we temporarily create a new slot to store the converted
tuple. However, we missed to drop such temporary slots, leading to
resource leakage.

Reported-by: Bowen Shi
Author: Hou Zhijie
Reviewed-by: Amit Kapila
Backpatch-through: 15
Discussion: https://postgr.es/m/CAM_vCudv8dc3sjWiPkXx5F2b27UV7_YRKRbtSCcE-pv=cVACGA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3e53492aa7084bceaa92757c90e067d79768797e

Modified Files
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src/backend/replication/pgoutput/pgoutput.c | 10 ++++++++++
1 file changed, 10 insertions(+)