fix: refresh error spam on direct_state (no lb) (#456)

* fix: refresh error spam on direct_state (no lb)

* chore: formatting connection module

---------

Co-authored-by: joeri dijkstra <joeri.dijkstra@bettyblocks.com>

Author: JoeriDijkstra

lib/grpc/client/connection.ex

@@ -273,7 +273,8 @@ defmodule GRPC.Client.Connection do
         :refresh,
         %{lb_mod: lb_mod, lb_state: lb_state, real_channels: channels, virtual_channel: vc} =
           state
-      ) do
+      )
+      when not is_nil(lb_mod) do
     {:ok, {prefer_host, prefer_port}, new_lb_state} = lb_mod.pick(lb_state)
 
     channel_key = "#{prefer_host}:#{prefer_port}"
@@ -294,6 +295,8 @@ defmodule GRPC.Client.Connection do
     end
   end
 
+  def handle_info(:refresh, state), do: {:noreply, state}
+
   def handle_info({:DOWN, _ref, :process, pid, reason}, state) do
     Logger.warning(
       "#{inspect(__MODULE__)} received :DOWN from #{inspect(pid)} with reason: #{inspect(reason)}"