[ci] Execute build.ps1 from bash on Mac to avoid STDIO streams hang (#…

…19257)

* Use Start-Process to run build.ps1

* Show Start-Process command

* Fix: Comma separator prior to -Script argument

* Dedicated .cake parameter setting for -Script

* Fix: Start-Process: Start 3rd parameter with a quote and not an escaped quote

* Execute build.ps1 under pwsh in bash

* Remove references to Start-Process since that solution did not work

* Execute build.ps1 from bash on Mac only

eng/pipelines/common/device-tests-steps.yml

@@ -55,9 +55,30 @@ steps:
     - pwsh: ./build.ps1 --target=dotnet-buildtasks --configuration="Release"
       displayName: 'Build the MSBuild Tasks'
 
-  - pwsh: ./build.ps1 -Script eng/devices/${{ parameters.platform }}.cake --project="${{ parameters.path }}" --device=${{ parameters.device }} --packageid=${{ parameters.windowsPackageId }} --results="$(TestResultsDirectory)" --binlog="$(LogDirectory)" ${{ parameters.cakeArgs }}
+  - pwsh: |
+      $platformName = 'Windows'
+      if ($IsMacOS) {
+        $platformName = 'Mac'
+      } elseif ($IsLinux) {
+        $platformName = 'Linux'
+      }
+      Write-Host "Platform.Name: ${platformName}"
+      Write-Host "##vso[task.setvariable variable=Platform.Name]${platformName}"
+    displayName: 'Set Platform.Name'
+
+  - pwsh: |
+      ./build.ps1 -Script eng/devices/${{ parameters.platform }}.cake --project="${{ parameters.path }}" --device=${{ parameters.device }} --packageid=${{ parameters.windowsPackageId }} --results="$(TestResultsDirectory)" --binlog="$(LogDirectory)" ${{ parameters.cakeArgs }}
+    displayName: $(Agent.JobName)
+    workingDirectory: ${{ parameters.checkoutDirectory }}
+    condition: and(succeeded(), ne(variables['Platform.Name'], 'Mac'))
+    retryCountOnTaskFailure: 2
+
+  - bash: |
+      # Execute the powershell script from a bash shell on Mac to avoid interference between powershell processes that lead to this error: The STDIO streams did not close within 10 seconds of the exit event from process '/usr/local/bin/pwsh'. This may indicate a child process inherited the STDIO streams and has not yet exited.
+      pwsh ./build.ps1 -Script eng/devices/${{ parameters.platform }}.cake --project="${{ parameters.path }}" --device=${{ parameters.device }} --packageid=${{ parameters.windowsPackageId }} --results="$(TestResultsDirectory)" --binlog="$(LogDirectory)" ${{ parameters.cakeArgs }}
     displayName: $(Agent.JobName)
     workingDirectory: ${{ parameters.checkoutDirectory }}
+    condition: and(succeeded(), eq(variables['Platform.Name'], 'Mac'))
     retryCountOnTaskFailure: 2
 
   - task: PublishTestResults@2