[clang] Add test for CWG392 (#87744)

[CWG392](https://cplusplus.github.io/CWG/issues/392.html) "Use of full
expression lvalue before temporary destruction". We're testing that
`operator bool()` is called before destructor of `C`.

I'm also marking CWG388 as requiring libc++abi test instead of codegen
test, as we need to test matching between exception object and exception
handlers.