Fix migration timestamp type

lib/pleroma/repo.ex

@@ -3,7 +3,10 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Repo do
-  use Ecto.Repo, otp_app: :pleroma, adapter: Ecto.Adapters.Postgres
+  use Ecto.Repo,
+    otp_app: :pleroma,
+    adapter: Ecto.Adapters.Postgres,
+    migration_timestamps: [type: :naive_datetime_usec]
 
   @doc """
   Dynamically loads the repository url from the