[SILGen] lower camel case on enum cases in a few tests

[nordicio]

Tests were using an old Swift naming convention for enum cases, now there are some fewer.

@slavapestov

[CodaFi]

Thanks for the patch, but there's a few thousand enum cases sprinkled throughout the test suite that share this problem and it would be pretty noisy if we were to start migrating them. The test here is meant to exercise code paths in the compiler, so sticking to a style guide, while important, isn't a primary concern here.

[nordicio]

I understand. :)

I had a brief discussion with @slavapestov about it here: https://twitter.com/slava_pestov/status/1075002706316705792

“Finally got it working - just to discover that it's being used everywhere. 😆 Is there any value in converting the tests to use the current convention?”

If there is value to it, it could be a way for me to learn more about the architecture while contributing something. But I understand if there isn’t.

[slavapestov]

@swift-ci Please smoke test and merge