[clang-tidy] support unscoped enumerations in readability-static-accessed-through-instance

fixed [60810](https://github.com/llvm/llvm-project/issues/60810)
unscoped enumerations in class can also be checked by `readability-static-accessed-through-instance`
add matcher for `enumConstantDecl` to match format
```
struct {
    enum { E1 };
};
```
The filter of member expression and the fix hint should be same as other condition.

Reviewed By: PiotrZSL

Differential Revision: https://reviews.llvm.org/D147315