How can I add a timestamp to all problems in zalando problem-spring-web?

Question

I want to add a timestamp to all default and custom problems like this:

{
  "title": "Internal Server Error",
  "status": 500,
  "detail": "An error occurred",
  "timestamp": "2023-04-13T22:30:00Z"
}

How can I add a custom field to all problems globally?