OutgoingMessage should set writable false

[ronag]

In #33131 we aligned OutgoingMessage to properly set the destroyed property. We should do the same for writable in order to properly align with streams.

[qballer]

Hey, I would like to work on the PR as the first contribution to Node. Will be working on this tonight

[mcollina]

@qballer I'm sorry but there seems to be a PR already open for this :(.