Pass the correct configuration arg

src/Tools/MicroBuild/Build.proj

@@ -37,7 +37,7 @@
     <MSBuild Projects="$(RepoRoot)src\NuGet\NuGet.proj" />
     <MSBuild Projects="$(RepoRoot)src\Setup\SetupStep2.proj" Properties="$(SetupStep2Properties);DeployExtension=false" />
 
-    <Exec Command="powershell -noprofile -executionPolicy ByPass -file $(RepoRoot)build\scripts\build.ps1 -testDesktop -msbuildDir &quot;$(MSBuildBinPath)&quot;" Condition="'$(SkipTest)' != 'true'" />
+    <Exec Command="powershell -noprofile -executionPolicy ByPass -file $(RepoRoot)build\scripts\build.ps1 -testDesktop $(ConfigurationArg) -msbuildDir &quot;$(MSBuildBinPath)&quot;" Condition="'$(SkipTest)' != 'true'" />
 
     <Exec Command="powershell -noprofile -executionPolicy ByPass -file $(MSBuildThisFileDirectory)..\..\..\build\scripts\check-toolset-insertion.ps1 &quot;$(MSBuildThisFileDirectory)..\..\..&quot; &quot;$(BinariesPath)&quot;" />