Add .NET 5 SDK for Azure Pipelines

Author: Turnerj

azure-pipelines.yml

@@ -11,7 +11,11 @@ jobs:
 
   steps:
   - task: UseDotNet@2
-    displayName: Install .NET SDK
+    displayName: Install .NET 5 SDK
+    inputs:
+      version: 5.0.x
+  - task: UseDotNet@2
+    displayName: Install .NET 6 SDK
     inputs:
       version: 6.0.x