Custom ACME Provider Support

[marcohald]

Feature Description

It would be nice to provide a Config Opton for a Custom ACME Provider such as StepCa .

Screenshots

No response

[LecrisUT]

@marcohald The implementation is up at #18340 if you want to test it. Personally I would go for a reverse-proxy solution, but you do you. Let me know if there's anything missing.