stream-clone-test: simplify the test for getbundle with stream=1 The core of this tests is about checking we receive a stream bundle with such request. We don't need to look at too much of the details of the stream itself. Since the content of the stream if shifting overtime, Such check is very fragile and consume a lot of time for little value when adjusting formats, caches, and protocol. So we reduce the size of what we check to focus on "is this a stream clone" question.