Teach pg_dump about the new pg_subscription.subrunasowner option.

Teach pg_dump about the new pg_subscription.subrunasowner option.

Among numerous other oversights, commit 482675987 neglected to fix
pg_dump to dump this new subscription option.  Since the new default
is "false" while the previous behavior corresponds to "true", this
would cause legacy subscriptions to silently change behavior during
dump/reload or pg_upgrade.  That seems like a bad idea.  Even if it
was intended, failing to preserve the option once set in a new
installation is certainly not OK.

While here, reorder associated stanzas in pg_dump to match the
field order in pg_subscription, in hopes of reducing the impression
that all this code was written with the aid of a dartboard.

Back-patch to v16 where this new field was added.

Philip Warner (cosmetic tweaks by me)

Discussion: https://postgr.es/m/20231027042539.01A3A220F0A@thebes.rime.com.au