pgsql: Fix ALTER SUBSCRIPTION grammar ambiguity

Fix ALTER SUBSCRIPTION grammar ambiguity

There was a grammar ambiguity between SET PUBLICATION name REFRESH and
SET PUBLICATION SKIP REFRESH, because SKIP is not a reserved word. To
resolve that, fold the refresh choice into the WITH options. Refreshing
is the default now.

Reported-by: tushar <tushar(dot)ahuja(at)enterprisedb(dot)com>

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/9907b55ceb17f55bb508a1f24027a57530d84442

Modified Files
--------------
doc/src/sgml/catalogs.sgml | 2 +-
doc/src/sgml/ref/alter_subscription.sgml | 35 ++++++++++++++++++++----------
src/backend/commands/subscriptioncmds.c | 34 +++++++++++++++++++++--------
src/backend/parser/gram.y | 14 ++----------
src/include/nodes/parsenodes.h | 1 -
src/test/regress/expected/subscription.out | 2 +-
src/test/regress/sql/subscription.sql | 2 +-
src/test/subscription/t/001_rep_changes.pl | 2 +-
8 files changed, 54 insertions(+), 38 deletions(-)