message: It should not be possible to create new streams in GoAway state.
diff: @@ -165,6 +165,15 @@ impl Http3Client {
  host,
  path
  );
  + // Requests cannot be created when a connection is in states: Initializing, GoingAway, Closing and Closed.
  + match self.base_handler.state() {
  + Http3State::GoingAway | Http3State::Closing(..) | Http3State::Closed(..) => {
  + return Err(Error::AlreadyClosed)
  + }
  + Http3State::Initializing => return Err(Error::Unavailable),
  + _ => {}
  + }
  +
  let id = self.conn.stream_create(StreamType::BiDi)?;
  self.base_handler.add_transaction(
  id,
  @@ -1948,6 +1957,13 @@ mod tests {
  assert!(stream_reset);
  assert_eq!(client.state(), Http3State::GoingAway);
  +
  + // Check that a new request cannot be made.
  + assert_eq!(
  + client.fetch("GET", "https", "something.com", "/", &[]),
  + Err(Error::AlreadyClosed)
  + );
  +
  client.close(now(), 0, "");
  }
  