Make expectThat(subject, block) return Unit

[RamazanYapparov]

Hi! Can you please consider making expectThat(subject, block) return Unit instead of DescribeableBuilder. Or add different Unit returning method with the same behaviour.

The problem is when using this method in test which body is basically runBlocking suspend block. In this case if the assertion is the last statement the block returns the DescribeableBuilder from the test method, and JUnit doesn't call non void (non Unit in this case) test methods during test phase.

[robfletcher]

Yeah, that seems reasonable. I'll check that it's not breaking anything vital.