Fix child checkable label attributes.
Fix child checkable label attributes.

mstaack/laravel-form-builder,barryvdh/laravel-form-builder,kristijanhusak/laravel-form-builder,tantam/laravel-form-builder,leohmoraes/laravel-form-builder,theshaunwalker/laravel-form-builder,Devitek/laravel-form-builder