Update dotnet-desktop.yml

.github/workflows/dotnet-desktop.yml

@@ -58,7 +58,7 @@ jobs:
       - name: Setup dotnet
         uses: actions/setup-dotnet@v3
         with:
-          dotnet-version: '6.0.x'
+          dotnet-version: '8.0.x'
 
 
       - name: Build solution