Update azure-pipelines.yml

azure-pipelines.yml

@@ -56,10 +56,9 @@ jobs:
 
   steps:
   - task: UseDotNet@2
-    displayName: 'Use .NET Core SDK 3.x'
+    displayName: 'Use .NET Core SDK 3.0.x'
     inputs:
-      version: 3.x
-      includePreviewVersions: true
+      version: 3.0.x
 
   - task: DotNetCoreCLI@2
     inputs: