Use correct to_remote script in counterparty commitments

Use correct to_remote script in counterparty commitments

While our commitment transactions did use the correct `to_remote`
script, the `ChannelMonitor`'s was not as it is tracked separately. This
would lead to users never receiving an `Event::SpendableOutputs` with a
`StaticPaymentOutput` descriptor to claim the funds.

Luckily, any users affected which had channel closures confirmed by a
counterparty commitment just need to replay the closing transaction to
receive the event.