2.x: TestSubscriber.requestMore missing

[davidmoten]

When I want to do backpressure testing on a Flowable with the Flowable.test(0) method I'm forced out of method chaining because request(n) is a void. Am I missing something? Shall I add a fluent requestMore(n)?

[akarnokd]

Yes, but don't forget to mark it as experimental.

[akarnokd]

Closing via #4838