refactor(credo): Refactor to appease new credo checks (complexity and logging)

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/notifier/email.ex

@@ -95,9 +95,8 @@ defmodule Mobilizon.Service.Notifier.Email do
   end
 
   defp can_send_activity?(activity, user, options) do
-    Logger.warn("Can't check if user #{inspect(user)} can be sent an activity",
-      activity: inspect(activity),
-      options: inspect(options)
+    Logger.warn(
+      "Can't check if user #{inspect(user)} can be sent an activity (#{inspect(activity)}) (#{inspect(options)})"
     )
 
     false