[Bug c++/109337] c++2a test concepts4.C passes when it should fail

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109337

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Reduced testcase:
```
template <class Ub> concept A42b = true;
template <class Tc> concept R42c = A42b<Tc&>;

static_assert (R42c<void>);
```


GCC does the right thing for too:
```
template <class Ub> bool A42b = true;
template <class Tc> concept R42c = A42b<Tc&>;

static_assert (!R42c<void>);
```