RolloutPlanTestCase makes invalid assumptions about test execution

RolloutPlanTestCase.testMaxFailServersRolloutPlan() assumes that the final op it sends (to remove the http-listener) will be executed on servers main-two and main-three. This is invalid, because if main-one executes before either main-two or main-three, there will be two failed servers in the rollout and the 3rd server will never get called.

This is why the test fails on JDK 8. There is some impl difference (probably in some collection class) that causes the server ops to be executed in different order.

This is just a matter of correcting some test assertions.