Revert "Autogen calendars"

This reverts commit e911217a83.

priv/repo/migrations/20230607151852_create_calendars.exs

@@ -1,15 +0,0 @@
-defmodule Osuuspuutarha.Repo.Migrations.CreateCalendars do
-  use Ecto.Migration
-
-  def change do
-    create table(:calendars) do
-      add :pickup_date, :date
-      add :is_picked_up, :boolean, default: false, null: false
-      add :order_id, references(:orders, on_delete: :nothing)
-
-      timestamps()
-    end
-
-    create index(:calendars, [:order_id])
-  end
-end