Upgrade setup-dotnet workflow action version

Author: peetw

.github/workflows/ci.yml

@@ -82,7 +82,7 @@ jobs:
         run: ${{ matrix.DB_INIT }}
 
       - name: Setup .NET
-        uses: actions/setup-dotnet@v3
+        uses: actions/setup-dotnet@v4
         with:
           dotnet-version: 6.0.x