Rejected promises show up as errors but keep a 200 status code

[sazzer]

If I use the following configuration:

    app.use(healthCheck({
        stats: {
            demo: () => Promise.reject(new Error('Its broke'))
        }
    }));

Then I get the following in the output:

  "errors": [
    "Its broke"
  ]

But I still get a Status Code of 200, instead of a 500 like I'd expect.