test(hls): use promise instead of done fix error message when test fails
test(hls): use promise instead of done fix error message when test fails

since playback.on method is wrapped by a try catch, when an error happens the catch handler of
events class will do not call done and the test will fail because there is a timeout and not because
the assetion fails. With a promise it will do not happen

clappr/clappr,clappr/clappr,clappr/clappr