pgsql: Doc: Clarify the behavior of triggers/rules in a logical subscri

Doc: Clarify the behavior of triggers/rules in a logical subscriber.

By default, triggers and rules do not fire on a logical replication
subscriber based on the "session_replication_role" GUC being set to
"replica". However, the docs in the logical replication section assumed
that the reader understood how this GUC worked. This modifies the docs to
be more explicit and links back to the GUC itself.

Author: Jonathan Katz, Peter Smith
Reviewed-by: Vignesh C, Euler Taveira
Backpatch-through: 11
Discussion: https://postgr.es/m/5bb2c9a2-499f-e1a2-6e33-5ce96b35cc4a@postgresql.org

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/19867d5f2d5ff3b9c4d791fd9f8b37292255adb6

Modified Files
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doc/src/sgml/logical-replication.sgml | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)