support for dotnet9 compilation

.gitea/workflows/test-dotnet.yaml

@@ -21,7 +21,7 @@ jobs:
     - name: Setup .NET
       uses: https://github.com/actions/setup-dotnet@v3
       with:
-        dotnet-version: 8.x
+        dotnet-version: 9.x
 
     - name: Restore dependencies
       run: dotnet restore
@@ -30,12 +30,12 @@ jobs:
       run: dotnet build --no-restore
 
     - name: Test
-      run: dotnet test --no-build --verbosity normal --logger trx --results-directory "TestResults-8.x"
+      run: dotnet test --no-build --verbosity normal --logger trx --results-directory "TestResults-9.x"
 
     - name: Upload dotnet test results
       uses: actions/upload-artifact@v3
       with:
-        name: dotnet-results-8.x
-        path: TestResults-8.x
+        name: dotnet-results-9.x
+        path: TestResults-9.x
         if: ${{ always() }}
         retention-days: 30