Remove unused functions

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

lib/web/cache/cache.ex

@@ -10,21 +10,9 @@ defmodule Mobilizon.Web.Cache do
   alias Mobilizon.Resources.Resource
   alias Mobilizon.Todos.{Todo, TodoList}
   alias Mobilizon.Web.Cache.ActivityPub
-  import Mobilizon.Service.Guards, only: [is_valid_string: 1]
-
-  @caches [:activity_pub, :feed, :ics]
 
   @type local_actor :: %Actor{domain: nil}
 
-  @doc """
-  Clears all caches for a local actor.
-  """
-  @spec clear_cache(%Actor{domain: nil, preferred_username: String.t()}) :: :ok
-  def clear_cache(%Actor{preferred_username: preferred_username, domain: nil})
-      when is_valid_string(preferred_username) do
-    Enum.each(@caches, &Cachex.del(&1, "actor_" <> preferred_username))
-  end
-
   @spec get_actor_by_name(binary) :: {:commit, Actor.t()} | {:ignore, nil}
   defdelegate get_actor_by_name(name), to: ActivityPub
   @spec get_local_actor_by_name(binary) :: {:commit, Actor.t()} | {:ignore, nil}