Do object insertion through Cachex

So we don't flood our postgres logs with errors. Should also make things
slightly faster.

lib/pleroma/web/twitter_api/twitter_api.ex

@@ -305,16 +305,8 @@ defmodule Pleroma.Web.TwitterAPI.TwitterAPI do
     else
       _e ->
         changeset = Object.context_mapping(context)
-
-        case Repo.insert(changeset) do
-          {:ok, %{id: id}} ->
-            id
-
-          # This should be solved by an upsert, but it seems ecto
-          # has problems accessing the constraint inside the jsonb.
-          {:error, _} ->
-            Object.get_cached_by_ap_id(context).id
-        end
+        {:ok, object} = Object.insert_or_get(changeset)
+        object.id
     end
   end