Add missing <EnableWindowsTargeting>true</EnableWindowsTargeting>

samples/interop/WindowsInteropTest/WindowsInteropTest.csproj

@@ -4,6 +4,7 @@
     <TargetFrameworks>net461;net6.0-windows</TargetFrameworks>
     <UseWPF>true</UseWPF>
     <UseWindowsForms>true</UseWindowsForms>
+    <EnableWindowsTargeting>true</EnableWindowsTargeting>
   </PropertyGroup>
 
   <ItemGroup>