pgsql: Fix signal handling in logical replication workers

Fix signal handling in logical replication workers

The logical replication worker processes now use the normal die()
handler for SIGTERM and CHECK_FOR_INTERRUPTS() instead of custom code.
One problem before was that the apply worker would not exit promptly
when a subscription was dropped, which could lead to deadlocks.

Author: Petr Jelinek <petr(dot)jelinek(at)2ndquadrant(dot)com>
Reported-by: Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9fcf670c2efdf31233d429f557ab77937f0f1e6a

Modified Files
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src/backend/replication/logical/launcher.c | 16 +++++++-------
src/backend/replication/logical/tablesync.c | 10 ++++-----
src/backend/replication/logical/worker.c | 34 ++++++++++++++++++++++++++---
src/backend/tcop/postgres.c | 5 +++++
src/include/replication/logicalworker.h | 2 ++
src/include/replication/worker_internal.h | 4 ----
6 files changed, 50 insertions(+), 21 deletions(-)