pgsql: Reorganize logical replication worker disconnect code

Reorganize logical replication worker disconnect code

Move the walrcv_disconnect() calls into the before_shmem_exit handler.
This makes sure the call is always made even during exit by signal, it
saves some duplicate code, and it makes the logic more similar to
walreceiver.c.

Author: Petr Jelinek <petr(dot)jelinek(at)2ndquadrant(dot)com>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/6812330f1cc95f258ffe4ce7d56bdd56efbd9fde

Modified Files
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src/backend/replication/logical/launcher.c | 6 ++++++
src/backend/replication/logical/tablesync.c | 1 -
src/backend/replication/logical/worker.c | 8 --------
3 files changed, 6 insertions(+), 9 deletions(-)