src: clean up `StreamPipe` in destructor

In the presence of Workers, it is not safe to assume that
`StreamPipe::Unpipe()` has been called at the time when the object
is destroyed.

Instead, clean up when the destructor is called.

PR-URL: https://github.com/nodejs/node/pull/26256


Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>