tls: do not rely on 'drain' handlers in StreamWrap

`'drain'` event handlers may not be invoked if the stream
is currently finishing. Instead, use the fact that we know
when writes are active or not, and invoke the delayed shutdown
handler from our own after-write callback.

PR-URL: https://github.com/nodejs/node/pull/24290
Refs: https://github.com/nodejs/node/pull/24288
Refs: https://github.com/nodejs/node/pull/24075


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Ouyang Yadong <oyydoibh@gmail.com>