pgsql: Preserve firing-on state when cloning row triggers to partitions

Preserve firing-on state when cloning row triggers to partitions

When triggers are cloned from partitioned tables to their partitions,
the 'tgenabled' flag (origin/replica/always/disable) was not propagated.
Make it so that the flag on the trigger on partition is initially set to
the same value as on the partitioned table.

Add a test case to verify the behavior.

Backpatch to 11, where this appeared in commit 86f575948c77.

Author: Álvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>
Reported-by: Justin Pryzby <pryzby(at)telsasoft(dot)com>
Discussion: https://postgr.es/m/20200930223450.GA14848@telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/df80fa2ee50478391445cef03e42c1b3d64fccca

Modified Files
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src/backend/commands/tablecmds.c | 8 ++---
src/backend/commands/trigger.c | 30 ++++++++++++++----
src/include/commands/trigger.h | 5 +++
src/test/regress/expected/triggers.out | 56 ++++++++++++++++++++++++++++++++++
src/test/regress/sql/triggers.sql | 32 +++++++++++++++++++
5 files changed, 121 insertions(+), 10 deletions(-)