Update readme

README.md

@@ -21,7 +21,7 @@ Give your customer support team easy access to the information they need. See de
 1. Download the latest release .zip file: **[version 0.4.0](https://ms-vsts.gallery.vsassets.io/_apis/public/gallery/publisher/ms-vsts/extension/services-zendesk/1.0.1/assetbyname/apps/vsts-zendesk-app_0.4.0.zip)**
 1. From Zendesk, click the settings icon (gear)
 1. Under **Apps** click Manage.
-1. Click **Upload App**
+1. Click **Upload private app**
 1. Give the app a name.
 1. Browse to the location you saved the .zip release and select it.
 1. Provide your Visual Studio Team Services name and decide on a work item tag for Zendesk.