FIO-5003: fixed that the radio with the value "false" is not displaye…

…d in different templates (formio#4699)

src/components/radio/Radio.js

@@ -150,15 +150,16 @@ export default class RadioComponent extends Field {
   }
 
   getValueAsString(value) {
-    if (!value) {
-      return '';
-    }
     if (!_.isString(value)) {
       value = _.toString(value);
     }
 
     const option = _.find(this.component.values, (v) => v.value === value);
 
+    if (!value) {
+      return _.get(option, 'label', '');
+    }
+
     return _.get(option, 'label', '');
   }