Correct the artifact build & test paths for Base Image Auto Update (#…

…6223)

Corrected the questionable build path to be actually using the thing it is building. 

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builds/e2e/templates/e2e-setup-base-image-update-release.yaml

@@ -35,9 +35,9 @@ steps:
 
 - pwsh: |
     $testDir = '$(Build.SourcesDirectory)/test/Microsoft.Azure.Devices.Edge.Test'
-    dotnet build $testDir
+    dotnet build -c Release $testDir
 
-    $binDir = Convert-Path "$testDir/bin/Debug/netcoreapp3.1"
+    $binDir = Convert-Path "$testDir/bin/Release/netcoreapp3.1"
     Write-Output "##vso[task.setvariable variable=binDir]$binDir"
   displayName: Build tests