Add parallel (#5614)

Add parallel

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Co-authored-by: Haonan Tang <haonantang@microsoft.com>

Author: haonanttt

build/AzurePipelinesTemplates/WindowsAppSDK-RunTests-Steps.yml

@@ -210,4 +210,5 @@ steps:
     condition: succeededOrFailed()
     inputs:
       targetPath: '$(Build.SourcesDirectory)\TestOutput'
-      artifact: '$(System.StageName)_${{ parameters.ImageName }}_$(buildConfiguration)$(buildPlatform)_$(Agent.JobStatus)$(artifactAttempt)'
+      artifact: '$(System.StageName)_${{ parameters.ImageName }}_$(buildConfiguration)$(buildPlatform)_$(Agent.JobStatus)$(artifactAttempt)'
+      Parallel: true