Check if a refresh is permitted by comparing timestamps before attempting to insert an Oban job

It's better to avoid inserting an Oban job that will just be rejected if it's not expensive to check.

test/pleroma/web/mastodon_api/controllers/poll_controller_test.exs

@@ -29,13 +29,16 @@ defmodule Pleroma.Web.MastodonAPI.PollControllerTest do
       id = to_string(object.id)
       assert %{"id" => ^id, "expired" => false, "multiple" => false} = response
 
+      # Local activities should not generate an Oban job to refresh
+      assert activity.local
+
       refute_enqueued(
         worker: Pleroma.Workers.PollWorker,
         args: %{"op" => "refresh", "activity_id" => activity.id}
       )
     end
 
-    test "does not create oban job to refresh poll if activity is local", %{conn: conn} do
+    test "creates an oban job to refresh poll if activity is remote", %{conn: conn} do
       user = insert(:user, local: false)
       question = insert(:question, user: user)
       activity = insert(:question_activity, question: question, local: false)