woW it's a black magic behind test-agent. I just realized that I can use `this.sinon` so that we don't have to restore them later xD 

And in this case, I just only have one test in this suite (try to make it more clear), so there is no need for each test (because there is only one test in thie suite). But I like the black magic :fire: , let's use `this.sinon.*` in setup instead !