[clang] Apply FixIts to members declared via `using` in derived classes

FixIt don't switch to arrow in derrived members with `using`

Example code:
```
struct Bar {
  void foo();
};
struct Baz {
  using Bar::foo;
};
void test(Baz* ptr) {
  ptr.^
}

Reviewed By: kadircet

Differential Revision: https://reviews.llvm.org/D131088