Support `HTTPS` and `SVCB` RRs in `dns_get_record`

[schuetzm]

Description

These record types are used to delegate web services to CDNs and to implement Encrypted Client HELLO, among other things. A short introduction is here:
https://www.sobyte.net/post/2022-01/dns-svcb-https/

It would be nice if these RRs could be queried by dns_get_record.

[Ayesh]

I played with this to add those two RRs, with very rudimentary work so far. The format is a bit annoying to parse, given the range of parameters and not having a lot of examples to follow.

I don't want to hold anyone from working on this, but just letting you know that I might be able to work on this soon.