Fix code coverage after 1ES pools update. (Azure#18771)

* Fix code coverage after 1ES pools update.

* Windows_NT is the Agent.OS for WIndows.

eng/pipelines/templates/jobs/archetype-sdk-client.yml

@@ -348,7 +348,7 @@ jobs:
 
       - task: Maven@3
         displayName: 'Generate aggregate code coverage report'
-        condition: and(eq(variables['OsName'], 'Windows'), eq(variables['JavaTestVersion'], '1.11'), eq('${{ parameters.SDKType }}', 'client'))
+        condition: and(eq(variables['Agent.OS'], 'Windows_NT'), eq(variables['JavaTestVersion'], '1.11'), eq('${{ parameters.SDKType }}', 'client'))
         inputs:
           mavenPomFile: sdk/${{ parameters.ServiceDirectory }}/pom.xml
           options: -Pcoverage
@@ -410,7 +410,7 @@ jobs:
       # Azure DevOps only seems to respect the last code coverage result published, so only do this for Windows + Java LTS.
       # Code coverage reporting is setup only for Track 2 modules.
       - task: PublishCodeCoverageResults@1
-        condition: and(eq(variables['OsName'], 'Windows'), eq(variables['JavaTestVersion'], '1.11'), eq('${{ parameters.SDKType }}', 'client'))
+        condition: and(eq(variables['Agent.OS'], 'Windows_NT'), eq(variables['JavaTestVersion'], '1.11'), eq('${{ parameters.SDKType }}', 'client'))
         inputs:
           codeCoverageTool: JaCoCo
           summaryFileLocation: sdk/${{ parameters.ServiceDirectory }}/target/site/jacoco-aggregate/jacoco.xml