Install dotnet sdk if not installed (#2373)

vsts/pipelines/templates/_releaseStepTemplate.yml

@@ -114,10 +114,20 @@ steps:
     scriptPath: ./vsts/scripts/tagBuilderImagesForRelease.sh
   condition: and(succeeded(), eq(variables['ReleaseBuildImages'], 'true'))
 
-- task: UseDotNet@2
-  displayName: 'Use .NET Core sdk 7.x'
-  inputs:
-    version: 7.x
+- script: |
+    dotnet --version
+    if [ $? -ne 0 ]; then
+      echo "Failed to check dotnet version. Assuming not installed."
+    fi
+    # Check for installed .NET 7.x using package manager
+    dpkg --list | grep 'dotnet-sdk-7\.'
+    if [ $? -ne 0 ]; then
+      echo "dotnet 7.x is not installed. Installing..."
+      # Update package list and install .NET 7.x SDK
+      sudo apt-get update
+      sudo apt-get install -y dotnet-sdk-7.0
+    fi
+  displayName: 'Install Dotnet SDK 7 if not installed'
 
 - task: ShellScript@2
   displayName: 'Test runtime images for pme staging registry'