Fix exception in Publish unit test results step (microsoft#20007)

### Description
Test results files are all in RelWithDebInfo\RelWithDebInfo directory.
It's not necessary to stat the directory of _deps 

### Motivation and Context
Recently this exception in zip-nuget pipleine occurs many times.
`##[error]Error: Failed find: EPERM: operation not permitted, stat
'D:\a\_work\1\b\RelWithDebInfo\_deps\flatbuffers-src\java\src\test\java\DictionaryLookup'`

https://dev.azure.com/aiinfra/Lotus/_build/results?buildId=426981&view=logs&j=75fc0348-fe99-522b-3acb-90fd80ac5271&t=5d4ebcc1-bcde-574d-6f4e-8abd0f04ae4b

tools/ci_build/github/azure-pipelines/nuget/templates/dml-vs-2022.yml

@@ -188,7 +188,7 @@ stages:
           displayName: 'Publish unit test results'
           inputs:
             testResultsFiles: '**\*.results.xml'
-            searchFolder: '$(Build.BinariesDirectory)'
+            searchFolder: '$(Build.BinariesDirectory)\$(BuildConfig)\$(BuildConfig)'
             testRunTitle: 'Unit Test Run'
           condition: succeededOrFailed()