Hello there,
This code is setting up a Content-Type for DELETE requests without data.
The rfc states:
A payload within a DELETE request message has no defined semantics; sending a payload body on a DELETE request might cause some existing implementations to reject the request.
From this I get that a request without a payload shouldn't have a mandatory content type.
The solution seems pretty simple, just add a delete to the regex that checks the verb used. If you agree with what I stated I can open a PR for this.