pgsql: Fix replica identity check for a partitioned table.

Fix replica identity check for a partitioned table.

The current publisher code checks if UPDATE or DELETE can be executed with
the replica identity of the table even if it's a partitioned table. We can
skip checking the replica identity for partitioned tables because the
operations are actually performed on the leaf partitions (not the
partitioned table).

Reported-by: Brad Nicholson
Author: Hou Zhijie
Reviewed-by: Peter Smith, Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/CAMMnM%3D8i5DohH%3DYKzV0_wYuYSYvuOJoL9F5nzXTc%2ByzsG1f6rg%40mail.gmail.com

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/76d257925994556bb49a7ce13dcb4785fbe7f395

Modified Files
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src/backend/executor/execReplication.c    | 7 +++++++
src/test/regress/expected/publication.out | 2 ++
src/test/regress/sql/publication.sql      | 2 ++
3 files changed, 11 insertions(+)