Correct debug logging in DNS-over-HTTP transport

Logging there should use Log function to include the request ID if
present. Changes were made unintentionally during the refactoring to
eliminate usage of global logger.

This commits message restores the correct/old behavior.

config.go

@@ -552,7 +552,7 @@ func (uc *UpstreamConfig) newDOHTransport(ctx context.Context, addrs []string) *
 		if uc.BootstrapIP != "" {
 			dialer := net.Dialer{Timeout: dialerTimeout, KeepAlive: dialerTimeout}
 			addr := net.JoinHostPort(uc.BootstrapIP, port)
-			logger.Debug().Msgf("sending doh request to: %s", addr)
+			Log(ctx, logger.Debug(), "sending doh request to: %s", addr)
 			return dialer.DialContext(ctx, network, addr)
 		}
 		pd := &ctrldnet.ParallelDialer{}
@@ -566,7 +566,7 @@ func (uc *UpstreamConfig) newDOHTransport(ctx context.Context, addrs []string) *
 		if err != nil {
 			return nil, err
 		}
-		logger.Debug().Msgf("sending doh request to: %s", conn.RemoteAddr())
+		Log(ctx, logger.Debug(), "sending doh request to: %s", conn.RemoteAddr())
 		return conn, nil
 	}
 	runtime.SetFinalizer(transport, func(transport *http.Transport) {