Update helix.proj

Author: HaoK

eng/helix/helix.proj

@@ -89,7 +89,7 @@
       <_appRuntimeFiles Include="$(OutputPath)\AspNetCoreAppRuntimeHelixRaw\**\*.xml" />
     </ItemGroup>
 
-    <Copy SourceFiles="@(_appRuntimeFiles)" DestinationFiles="$(OutputPath)\AspNetCoreAppRuntimeHelix" />
+    <Copy SourceFiles="@(_appRuntimeFiles)" DestinationFolder="$(OutputPath)\AspNetCoreAppRuntimeHelix" />
     <ZipDirectory SourceDirectory="$(OutputPath)\AspNetCoreAppRuntimeHelix" DestinationFile="$(OutputPath)\AspNetCoreAppRuntimeHelix.zip" Overwrite="true" />
 
     <HelixCorrelationPayload Include="$(OutputPath)\AspNetCoreAppRuntimeHelix.zip" Destination="$(DotNetCliDestination)\shared\Microsoft.AspNetCore.App\$(SharedFxVersion)" />