Use correct parameter when running an example. (#358)

Author: katka-h

google-ads-examples/src/main/java/com/google/ads/googleads/examples/accountmanagement/GetAccountHierarchy.java

@@ -73,7 +73,7 @@ public static void main(String[] args) {
       // here if and only if the managerId is set. If the loginCustomerId is set neither on the
       // command line nor below, a null value will be passed to the run example method, and the
       // example will use each respective accessible customer ID as the loginCustomerId.
-      // params.managerId = Long.parseLong("INSERT_LOGIN_CUSTOMER_ID_HERE");
+      // params.loginCustomerId = Long.parseLong("INSERT_LOGIN_CUSTOMER_ID_HERE");
     }
 
     if (params.managerId != null && params.loginCustomerId == null) {