Use <Copy> in the PostBuild target instead of separate <Exec>s for mkdir and copy.

ILSpy/ILSpy.csproj

@@ -397,11 +397,13 @@
   (related to https://github.com/icsharpcode/ILSpy/issues/511)
   -->
   <Target Name="PostBuild" AfterTargets="PostBuildEvent">
-	  <Exec Command="mkdir ..\ILSpy.AddIn\packages\" IgnoreExitCode="true" />
-	  <Exec Command="copy &quot;$(TargetDir)\System.ValueTuple.dll&quot; ..\ILSpy.AddIn\packages\" />
-	  <Exec Command="copy &quot;$(TargetDir)\System.Collections.Immutable.dll&quot; ..\ILSpy.AddIn\packages\" />
-	  <Exec Command="copy &quot;$(TargetDir)\ICSharpCode.AvalonEdit.dll&quot; ..\ILSpy.AddIn\packages\" />
-    <Exec Command="copy &quot;$(TargetDir)\Humanizer.dll&quot; ..\ILSpy.AddIn\packages\" />
-    <Exec Command="copy &quot;$(TargetDir)\Mono.Cecil.dll&quot; ..\ILSpy.AddIn\packages\" />
+    <ItemGroup>
+      <NuGetPackagesToCopy Include="$(TargetDir)System.ValueTuple.dll" />
+      <NuGetPackagesToCopy Include="$(TargetDir)System.Collections.Immutable.dll" />
+      <NuGetPackagesToCopy Include="$(TargetDir)ICSharpCode.AvalonEdit.dll" />
+      <NuGetPackagesToCopy Include="$(TargetDir)Humanizer.dll" />
+      <NuGetPackagesToCopy Include="$(TargetDir)Mono.Cecil.dll" />
+    </ItemGroup>
+    <Copy SourceFiles="@(NuGetPackagesToCopy)" DestinationFolder="..\ILSpy.AddIn\packages" />
   </Target>
 </Project>