pgsql: Fix updating of pg_subscription_rel from workers

Fix updating of pg_subscription_rel from workers

A logical replication worker should not insert new rows into
pg_subscription_rel, only update existing rows, so that there are no
races if a concurrent refresh removes rows. Adjust the API to be able
to choose that behavior.

Author: Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>
Reported-by: tushar <tushar(dot)ahuja(at)enterprisedb(dot)com>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/644ea35fc1352d845299563c7ddfb8b524ed27d9

Modified Files
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src/backend/catalog/pg_subscription.c | 13 +++++++++----
src/backend/commands/subscriptioncmds.c | 4 ++--
src/backend/replication/logical/tablesync.c | 11 +++++++----
src/include/catalog/pg_subscription_rel.h | 2 +-
4 files changed, 19 insertions(+), 11 deletions(-)