pgsql: Restart the apply worker if the privileges have been revoked.

Restart the apply worker if the privileges have been revoked.

Restart the apply worker if the subscription owner's superuser privileges
have been revoked. This is required so that the subscription connection
string gets revalidated and use the password option to connect to the
publisher for non-superusers, if required.

Author: Vignesh C
Reviewed-by: Amit Kapila
Discussion: http://postgr.es/m/CALDaNm2Dxmhq08nr4P6G+24QvdBo_GAVyZ_Q1TcGYK+8NHs9xw@mail.gmail.com

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/79243de13f4d251309d7831744e98d6b965ed4d6

Modified Files
--------------
src/backend/catalog/pg_subscription.c       |  3 +++
src/backend/commands/subscriptioncmds.c     |  4 ++--
src/backend/replication/logical/tablesync.c |  6 ++----
src/backend/replication/logical/worker.c    | 33 ++++++++++++++++++++++++-----
src/include/catalog/pg_subscription.h       |  1 +
src/test/subscription/t/027_nosuperuser.pl  | 24 +++++++++++++++++++++
6 files changed, 60 insertions(+), 11 deletions(-)