[FR] Enabling DoH service without TLS certificates

[poscat0x04]

Current behavior
Currently unbound requires both tls-service-key and tls-service-pem to be set to provide DNS-over-TLS and DNS-over-HTTPS downstream. But unbound also provides the option to provide unencrypted DNS-over-HTTP service via http-notls-downstream. This means even if one want to provide only DNS-over-HTTP service, one has to provide TLS certificates which isn't ideal.

Describe the desired feature
Being able to provide DNS-over-HTTP service without TLS certificates.

Potential use-case
This feature is useful for anyone who wants to use unbound as a DoH server while using a reverse proxy such as nginx.

[gthess]

This is already available with the http-notls-downstream option.
Do you use a specific configuration that fails somehow? Do you have log output to share?