`specify_nonobvious_local_variable_types` false positive with typedefs + type args

```dart
class Foo {}
typedef Bar = Foo;

void main() {
  var b = Bar();
}
```

No problems with the above code.

<br>

But if we add a type argument:

```dart
class Foo<T> {}
typedef Bar = Foo<Object?>;

void main() {
  var b = Bar();
}
```

According to the linter rule, `b`'s type is no longer obvious.