bump idweb version to 2.15.1 (#246)

Author: kllysng

1. Desktop app calls Web API/TodoListService/TodoListService.csproj

@@ -7,6 +7,6 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Identity.Web" Version="2.13.3" />
+    <PackageReference Include="Microsoft.Identity.Web" Version="2.15.1" />
   </ItemGroup>
 </Project>

2. Web API now calls Microsoft Graph/TodoListService/TodoListService.csproj

@@ -11,8 +11,8 @@
   </ItemGroup>
 
   <ItemGroup>
-	  <PackageReference Include="Microsoft.Identity.Web.MicrosoftGraph" Version="2.13.3" />
-	  <PackageReference Include="Microsoft.Identity.Web" Version="2.13.3" />
+	  <PackageReference Include="Microsoft.Identity.Web.MicrosoftGraph" Version="2.15.1" />
+	  <PackageReference Include="Microsoft.Identity.Web" Version="2.15.1" />
   </ItemGroup>
 
 </Project>