Upsteam support for strict group strategy and parallel_best addresses

Howdy, love blocky. Would be great if you could setup up upstream groups to follow a strict order and inside the group the addressed were selected using parallel_best. This would allow you to support multiple DoH/DoT servers and only fallback to UDP if DoH/DoT failed. Maybe I am just over complicating it and DoH/DoT do not fail enough to justify a change like this.

upstreams:
  strategy: strict
  groups:
    # These will be tried first
    default:
      strategy: parallel_best
      - https://cloudflare-dns.com/dns-query
      - https://dns.google/dns-query
       
      - tcp-tls:1.1.1.1:853
      - tcp-tls:9.9.9.9:853
    fallback:
      strategy: parallel_best
      - 1.1.1.1
      - 9.9.9.9