Bump System.Text.Json from 10.0.12 to 10.0.13 - #6

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/setup-dotnet@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

This async method lacks 'Await' operators and so will run synchronously. Consider using the 'Await' operator to await non-blocking API calls, or 'Await Task.Run(...)' to do CPU-bound work on a background thread.

This async method lacks 'Await' operators and so will run synchronously. Consider using the 'Await' operator to await non-blocking API calls, or 'Await Task.Run(...)' to do CPU-bound work on a background thread.