feat: add support for none response_type

[dtam-cybozu]

This PR adds support for the none response_type specified in https://openid.net/specs/oauth-v2-multiple-response-types-1_0.html#none

Related Issue or Design Document

This was brought up before here https://github.com/ory/fosite/issues/409

Checklist

• [x] I have read the contributing guidelines and signed the CLA.
• [x] I have referenced an issue containing the design document if my change introduces a new feature.
• [x] I have read the security policy.
• [x] I confirm that this pull request does not address a security vulnerability. If this pull request addresses a security vulnerability, I confirm that I got approval (please contact security@ory.sh) from the maintainers to push the changes.
• [x] I have added tests that prove my fix is effective or that my feature works.
• [ ] I have added the necessary documentation within the code base (if appropriate).

Further comments

I still need to add non-unit tests but I'd prefer to do this after I've received confirmation that this feature and this approach is okay. This is also quite a small feature so perhaps extensive testing of it is not completely necessary - please let me know how much testing you're expecting for this!

I also need to add something to the changelog.