Update dotnet.yml

Author: AndrewClements84

.github/workflows/dotnet.yml

@@ -27,3 +27,9 @@ jobs:
 
     - name: Test with coverage
       run: dotnet test ./src/ByteFlow/ByteFlow.sln --no-build --configuration Release --collect:"XPlat Code Coverage"
+
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v4
+      with:
+        files: ./tests/ByteFlow.Tests/TestResults/**/*.xml
+        token: ${{ secrets.CODECOV_TOKEN }}