revert client side change

assets/javascripts/wizard/initializers/custom-wizard-field.js.es6

@@ -57,12 +57,6 @@ export default {
     ];
 
     FieldModel.reopen({
-      init() {
-        this._super(...arguments);
-        if (this.type === "checkbox") {
-          this.set("value", this.value || false);
-        }
-      },
       check() {
         if (this.customCheck) {
           return this.customCheck();