fix: clarify usage of ignoreFailedUpdates in CodePushOptions (#84)

Author: floydkim

typings/react-native-code-push.d.ts

@@ -48,6 +48,10 @@ export interface UpdateCheckResponse {
 }
 
 export interface CodePushOptions extends SyncOptions {
+    /**
+     * The `ignoreFailedUpdates` option is only available as an option for `CodePush.sync()`.
+     */
+    ignoreFailedUpdates?: never;
     /**
      * Specifies when you would like to synchronize updates with the CodePush server.
      * Defaults to codePush.CheckFrequency.ON_APP_START.