Change EndPointUri param name in Program.cs to EndpointUri as stated in App.config

.vs/ProjectSettings.json

@@ -0,0 +1,3 @@
+{
+  "CurrentProjectSetting": null
+}

src/Program.cs

@@ -30,7 +30,7 @@ public class Program
         /// <summary>
         /// The Azure DocumentDB endpoint for running this GetStarted sample.
         /// </summary>
-        private static readonly string EndpointUri = ConfigurationManager.AppSettings["EndPointUri"];
+        private static readonly string EndpointUri = ConfigurationManager.AppSettings["EndpointUri"];
 
         /// <summary>
         /// The primary key for the Azure DocumentDB account.