CSR-1023 update Concept code with code from ISS.

Tested site flow locally without issues.

src/digital-components/base-input-button/button-functionality-props.js

@@ -4,8 +4,15 @@ export const inputButtonProps = {
         required: true,
     },
     modelValue: {
-        type: [Array, String, Number],
         required: true,
+        validator: function(prop) {
+            return (
+                prop === null
+                || Array.isArray(prop)
+                || typeof prop === 'string'
+                || (typeof prop === 'number' && !Number.isNaN(prop))
+            )
+        }
     },
     isMultiSelect: Boolean,
     groupName: {