Remove Azure pipeline task to install .NET 8 runtime

azure-pipelines.yml

@@ -141,14 +141,6 @@ stages:
           displayName: Build and Deploy
           condition: succeeded()
 
-        # Needed for Microsoft.AspNetCore.Razor.Microbenchmarks.Generator tests
-        - task: UseDotNet@2
-          displayName: 'Install .NET 8 runtime'
-          inputs:
-            packageType: runtime
-            version: 8.x
-            installationPath: '$(Build.SourcesDirectory)\.dotnet'
-
         - script: eng\CIBuild.cmd
             -configuration $(_BuildConfig)
             -prepareMachine