Update testing.yml

Author: Infarh

.github/workflows/testing.yml

@@ -21,9 +21,14 @@ jobs:
     runs-on: windows-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v3
+        with:
+          dotnet-version: 8.0.x
 
       - name: Cache NuGet  
         uses: actions/cache@v3