[clang-tools-extra] [clang-tidy] support expect no diagnosis test (PR #91293)

[Danny Mösch via cfe-commits]

SimplyDanny wrote:

> If nothing is provided, then nothing can be detected.

And why is this not a valid test? No `CHECK-*` comments in the reference file, so no violations from `clang-tidy` are expected?

> `not` will treat non-zero return code as success. It is totally different thing.

👍 

https://github.com/llvm/llvm-project/pull/91293