ActivityPubTest: Update test for atomized parameters.

test/web/activity_pub/activity_pub_test.exs

@@ -621,7 +621,7 @@ test "doesn't return announce activities with blocked users in 'cc'" do
     assert {:ok, activity_three} = ActivityPub.insert(data)
 
     activities =
-      ActivityPub.fetch_activities([], %{"blocking_user" => blocker})
+      ActivityPub.fetch_activities([], %{blocking_user: blocker})
       |> Enum.map(fn act -> act.id end)
 
     assert Enum.member?(activities, activity_one.id)