with this change we're returning immutable headers of non stomp messages. That way timestamp and id of the message will be set. For stomp messages the headers still have to be mutable related to gh-276 fixes gh-978
with this change we're returning immutable headers of non stomp messages. That way timestamp and id of the message will be set. For stomp messages the headers still have to be mutable related to gh-276 fixes gh-978