[Workshop] - Modernizer - Error while starting the backend

There is an error that is generated in the console, when the backend service is started. The error is not stopping the application to work but it is causing some confusion to some workshop participants.

```
/backend$ npm run start

ERROR Cannot copy server address to clipboard: Couldn't find the `xsel` binary and fallback didn't work. On Debian/Ubuntu you can install xsel with: sudo apt install xsel.
```

Start by running `npm run start` from the `/backend` directory and trace where the server address is sent to the clipboard. Confirm whether the startup path can avoid the xsel error while keeping the backend running and the console output clear.

Written by the indexing model from the issue text.