request does not unsusbcribe on timeout when noMux=true

[davidgf]

I'm using the JS nats@2.26.0 library, along with the nats:2.10.14 docker image. I'm noticing a behaviour I didn't anticipate with the request-reply pattern. Considering the following snippet:

const response = await natsConnection
  .request(`requests.${msgId}`, jsonCodec.encode(message), {
    timeout,
    noMux: true,
    reply: `responses.${msgId}`,
  })
  .catch((err) => {
    console.error(err, 'Error sending NATS message');
    throw err.code === ErrorCode.Timeout ? new Error('Timeout') : new Error('Another kind of error');
  });

When there's a timeout error, the cli command nats server report connections reports a continuously increasing number of subscriptions. When the .request() call succeeds, this doesn't happen and the number of subscriptions remains stable. This leads me to think that the underlying subscription created by the .request() method on the reply subject is not closed automatically on timeout. If my analysis is correct and I'm not misinterpreting the reports, I wanted to know if this is the expected behaviour.
If so, I would also like to know how the subscription should be closed.

[aricart]

This is fixed by nats-io/nats.deno#715