404 error is not returning body as json

[oborba]

When we do a post request with a invalid url like it: ("myapp.com/servers/localhost/zonessssss")

The return body is not a json, it is a plain text.

Possible cause : https://github.com/PowerDNS/pdnscontrol/blob/966347f85cf127b8c51bbe939fbf0b15c39b5d23/pdnscontrol/init.py#L90