Update MfaSmsList.mdx

Author: BcnCarlos

main/docs/libraries/acul/js-sdk/Screens/classes/MfaSmsList.mdx

@@ -117,7 +117,7 @@ Optional payload for the action.
 Additional data collected from the user.
 </ParamField>
 
-<ParamField body='index' type='number'>
+<ParamField body='index' type='number' required>
 The index of the phone number to select.
 </ParamField>