CREATE SUBSCRIPTION -- add missing tab-completes

There are some recent comment that added new options for CREATE SUBSCRIPTION

"Add new predefined role pg_create_subscription." [1]
This added a new "password_required" option.

"Add a run_as_owner option to subscriptions." [2]
This added a "run_as_owner" option.

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AFAICT the associated tab-complete code was accidentally omitted.

PSA patches to add those tab completions.

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[1] https://github.com/postgres/postgres/commit/c3afe8cf5a1e465bd71e48e4bc717f5bfdc7a7d6
[2] https://github.com/postgres/postgres/commit/482675987bcdffb390ae735cfd5f34b485ae97c6

Kind Regards,
Peter Smith.
Fujitsu Australia