[clang] [clang][ssaf] Add JSONFormat support for WPASuite (PR #187403)

[Aviral Goel via cfe-commits]

aviralg wrote:

I moved all the WPASuite lit tests into a subdirectory. We will follow this pattern and create TUSummary and LUSummary sibling directories for their lit tests.

https://github.com/llvm/llvm-project/pull/187403