Merge pull request #25054 from dotnet/marcpopMSFT-teststability

Reduce parallel copies of the test .zip file that were overlapping

Author: marcpopMSFT

src/Tests/Microsoft.NET.Sdk.Publish.Tasks.Tests/Microsoft.NET.Sdk.Publish.Tasks.Tests.csproj

@@ -34,7 +34,7 @@
 
   <ItemGroup>
     <None Include="Resources\TestPublishContents.zip">
-      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
   </ItemGroup>