Some of our API types contain fields that get rendered very poorly by
gomega.format.Object because they contain lots of internal information, for
example CreationTimestamp. As a result, dumping full API object typically gets
truncated.
What we want is a representation that is a) multi-line (in contrast to the
stringer implemented by our types) and b) drops empty fields where it
was defined that this is okay.
The normal YAML representation fits that requirement. We just need to teach
gomega how and when to do that. This cannot be done for each type through a
generated GomegaString method (lots of code, additional dependency in public
API on YAML encoder), but it can be done inside tests by adding a formatting
handler (new gomega feature).
