Improve 'Expecting code to raise a throwable' when lambda returns a value

[findepi]

assertThatThrownBy throws "Expecting code to raise a throwable" when called code doesn't throw.
When test assertion fails, it's tempting to know what did the code do instead.

Enhance "Expecting code to raise a throwable" to mention produced value in case when the lambda is a producer.

[scordio]

The related change has been reverted in #3318 and the topic should be evaluated again together with #1652 and #2519.

[findepi]

@scordio apologies for #3314 and thank you for the quick revert.

[scordio]

No problem at all, @findepi! Unfortunately, we missed that potential breaking change but now we learned 🙂

[sbrannen]

• Related to Regression: assertThrows() ThrowingSupplier variants break existing code junit-team/junit5#1576