fix(updater): only uses DoH to cloudflare+google

- prevent dns plaintext manipulation both the periodic update and when running in cli mode
- possibly higher reliability on poor connections versus UDP
- drop `-dns` flag in update command
- for now no configuration allowed since it makes everything rather complex

internal/updater/resolver/repeat.go

@@ -14,9 +14,9 @@ type Repeat struct {
 	resolver *net.Resolver
 }
 
-func NewRepeat(resolverAddress string) *Repeat {
+func NewRepeat(dialer Dialer) *Repeat {
 	return &Repeat{
-		resolver: newResolver(resolverAddress),
+		resolver: newResolver(dialer),
 	}
 }