pgsql: Mark some columns in pg_subscription as NOT NULL.

Mark some columns in pg_subscription as NOT NULL.

In pg_subscription, subconninfo, subslotname, subsynccommit and
subpublications are expected not to be NULL. Therefore this patch
adds BKI_FORCE_NOT_NULL markings to them.

This patch is basically unnecessary unless the code has a bug which
wrongly sets either of those columns to NULL. But it's good to have
this as a safeguard.

Author: Masahiko Sawada
Reviewed-by: Kyotaro Horiguchi
Reported-by: Fujii Masao
Discussion: http://postgr.es/m/CAHGQGwFDWh_Qr-q_GEMpD+qH=vYPMdVqw=ZOSY3kX_Pna9R9SA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/88b0a31926331eb5336ec92010b3b4f7e6efb53c

Modified Files
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src/include/catalog/pg_subscription.h | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)