[FormBuilderRadioGroup]: No way to decrease padding of Radio widget

### Is there an existing issue for this?

- [X] I have searched the existing issues

### Package/Plugin version

9.2.1

### What you'd like to happen

```Markdown
It would be great to be able to specify size of Radio or set VisualDensity, but probably both parameters, because Radio takes too much space by default.
```

### Alternatives you've considered

```Markdown
Currently I have to create radio group by myself using ListView.separated and to wrap each Radio in a SizedBox with explicit height and to add visual density.
```

### Aditional information

Too much padding

Ok padding