pgsql: Close relations opened specifically for AFTER triggers

Close relations opened specifically for AFTER triggers

39dcfda2d fixed an incorrect reuse of ResultRelInfos for AFTER triggers
when the ResultRelInfo needed to have a different ri_RootResultRelInfo.
That caused an issue in logical replication apply workers as
finish_edata() neglects to call ExecCloseResultRelations() and instead
relies on ExecCleanupTupleRouting() to close relations opened during
partitioning's tuple routing. Since 39dcfda2d, because we may have done
some additional table_opens() calls due to having to create an additional
ResultRelInfo because of requirements to have a different
ri_RootResultRelInfo, we should now be explicitly closing any relations
opened on ResultRelInfos in EState's es_trig_target_relations.

Since finish_edate() seems to want to avoid calling
ExecCloseResultRelations(), add a new external function named
ExecCloseTrigTargetRelations().

Reported-by: Hayato Kuroda (Fujitsu) <kuroda(dot)hayato(at)fujitsu(dot)com>
Author: Hayato Kuroda (Fujitsu) <kuroda(dot)hayato(at)fujitsu(dot)com>
Author: David Rowley <dgrowleyml(at)gmail(dot)com>
Reviewed-by: Zhijie Hou (Fujitsu) <houzj(dot)fnst(at)fujitsu(dot)com>
Discussion: https://postgr.es/m/OS9PR01MB121491E7E05950D108AF9A6D8F5A72@OS9PR01MB12149.jpnprd01.prod.outlook.com
Backpatch-through: 15

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c949e6524c0f306513176e8f96bd8b4bdd49d667

Modified Files
--------------
src/backend/executor/execMain.c | 16 ++++++++++++++++
src/backend/replication/logical/worker.c | 12 ++++++++----
src/include/executor/executor.h | 1 +
src/test/subscription/t/013_partition.pl | 7 +++++++
4 files changed, 32 insertions(+), 4 deletions(-)