pgsql: Invalidate pgoutput's replication-decisions cache upon schema re

Invalidate pgoutput's replication-decisions cache upon schema rename.

A schema rename should cause reporting the new qualified names of
tables to logical replication subscribers, but that wasn't happening.
Flush the RelationSyncCache to make it happen.

(If you ask me, the new test case shows that the behavior in this area
is still pretty dubious, but apparently it's operating as designed.)

Vignesh C

Discussion: https://postgr.es/m/CALDaNm32vLRv5KdrDFeVC-CU+4Wg1daA55hMqOxDGJBzvd76-w@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cd4b2334db4980bbf86a8ba1d446db17e62ca342

Modified Files
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src/backend/replication/pgoutput/pgoutput.c | 25 ++++++++---
src/test/subscription/t/100_bugs.pl         | 65 ++++++++++++++++++++++++++++-
2 files changed, 84 insertions(+), 6 deletions(-)