Update GitHub Actions workflow with permissions and validation

Added permissions for id-token, contents, and issues. Included a step to validate Workload Identity authentication.

Author: dcasati

.github/workflows/copilot-setup-steps.yml

@@ -5,6 +5,11 @@ name: "Copilot Setup Steps"
 on:
   workflow_dispatch:
 
+permissions:
+  id-token: write
+  contents: read
+  issues: write
+
 env:
   ARM_CLIENT_ID: ${{ secrets.ARM_CLIENT_ID }}
   ARM_SUBSCRIPTION_ID: ${{ secrets.ARM_SUBSCRIPTION_ID }}
@@ -37,3 +42,8 @@ jobs:
           client-id: ${{ secrets.ARM_CLIENT_ID }}
           tenant-id: ${{ secrets.ARM_TENANT_ID }}
           subscription-id: ${{ secrets.ARM_SUBSCRIPTION_ID }}
+      
+      - name: Validate Workload Identity Auth Works
+        run: |
+          az account show
+          az group list