Allow list for sanitised errors

[thomasverleye]

All errors that are thrown to the client get sanitised to prevent leaking sensitive data.

It would be great to have the ability to add a configuration to allow certain attributes in an Error object.

The use-case for having this is because we want to share a correlation id and a certain error code from the original request that has happened (if available).

Now we're throwing this data with a status 500 and have to manually throw it to our error tracking (Sentry).