chore(updater): create resolver in provider updater

- Pass min servers to resolve call
- Set settings when constructing resolver
- Construct resolver in each provider updater
- No more common resolver for all providers

internal/provider/ivpn/updater/servers.go

@@ -38,7 +38,7 @@ func (u *Updater) FetchServers(ctx context.Context, minServers int) (
 			common.ErrNotEnoughServers, len(hosts), minServers)
 	}
 
-	hostToIPs, warnings, err := resolveHosts(ctx, u.presolver, hosts, minServers)
+	hostToIPs, warnings, err := u.presolver.Resolve(ctx, hosts, minServers)
 	for _, warning := range warnings {
 		u.warner.Warn(warning)
 	}