Improvements to group page

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

lib/service/export/icalendar.ex

@@ -48,7 +48,7 @@ defmodule Mobilizon.Service.Export.ICalendar do
   """
   @spec export_public_actor(Actor.t()) :: String.t()
   def export_public_actor(%Actor{} = actor) do
-    with true <- Actor.is_public_visibility(actor),
+    with {:visibility, true} <- {:visibility, Actor.is_public_visibility?(actor)},
          %Page{elements: events} <-
            Events.list_public_events_for_actor(actor) do
       {:ok, %ICalendar{events: events |> Enum.map(&do_export_event/1)} |> ICalendar.to_ics()}