update ci pipeline to use dotnet 8,9,10

Author: gavinbarron

.github/workflows/validatePullRequest.yml

@@ -22,7 +22,10 @@ jobs:
       - name: Setup .NET
         uses: actions/[email protected]
         with:
-          dotnet-version: 8.x
+          dotnet-version: | 
+            8.0.x
+            9.0.x
+            10.x
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v4
         with: