[Eng] Fix dotnet test not working (#28563)

Author: VeryEarly

.azure-pipelines/PipelineSteps/test-steps.ps1

@@ -36,10 +36,9 @@ $buildArgs = "/p:Configuration=$Configuration;TestFramework=$TestFramework"
 
 if ($IsLinux) {
     # Applying various parallelism/heap restriction behaviors to prevent OOM issues on Ubuntu 24.04
-    Write-Host -ForegroundColor Yellow "Detected Linux agent – applying memory tuning for tests"
+    Write-Host -ForegroundColor Yellow "Detected Linux agent - applying memory tuning for tests"
     $env:DOTNET_gcServer = "0"
     $env:DOTNET_gcHeapCount = "2"
-    $buildArgs += ";RunConfiguration.MaxCpuCount=2"
 }
 
 dotnet msbuild $buildProjPath /t:Test $buildArgs
@@ -86,4 +85,4 @@ if ($FailedModuleList.Length -ne 0)
 }
 
 Set-Location $currentPath
-Write-Host -ForegroundColor DarkGreen "-------------------- End checking test status ... --------------------`n`n`n`n`n"
+Write-Host -ForegroundColor DarkGreen "-------------------- End checking test status ... --------------------`n`n`n`n`n"