Update dotnet.yml

Author: sir-gon

.github/workflows/dotnet.yml

@@ -26,3 +26,7 @@ jobs:
       run: dotnet build --no-restore
     - name: Test
       run: dotnet test --no-build --verbosity normal
+    - name: Upload coverage reports to Codecov
+      uses: codecov/codecov-action@v4.0.1
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}