Manuel Bucher

Either * send the updated priority as a response header * or update the [function that sets a response](https://github.com/mozilla/neqo/blob/37bb62fa7b43ac624406090ba4f94f4cc082790b/neqo-http3/src/server_events.rs#L54) or better both Originally posted by @ddragana in https://github.com/mozilla/neqo/pull/1200#discussion_r699209599_