False positive of uninitialized base in cppcoreguidelines-pro-type-member-init

```cpp
struct S;  // forward declaration is needed

struct S
{
     int a;
};

struct C : S
{
    C() : S{0} {}
};
```

```
<source>:10:5: warning: constructor does not initialize these bases: S [cppcoreguidelines-pro-type-member-init]
   10 |     C() : S{0} {}
      |     ^
      |           S(),
1 warning generated.
```

https://godbolt.org/z/7b8cTP7G7