Fail performance test iteration fast (#7777)This fixes https://github.com/gradle/gradle-private/issues/1393Previously, we collect all exceptions in the performance test execution then `assertEveryBuildSucceeds()`. This doesn't make any sense - we don't need to run the test any more if there's a failure. This PR fixes this issue by failing fast in performance iterations. Also, we have 4 kinds of checks, which makes things complicated. This PR removes them and use `true/false` instead.