Fixed registered field having wrong timezone

This happened with at least Postgres, which took it's server's timezone. It's complicated. Let's just set it from our side instead where we have some control.

spoolman/database/filament.py

@@ -2,6 +2,7 @@
 
 import logging
 from collections.abc import Sequence
+from datetime import datetime
 from typing import Optional, Union
 
 from sqlalchemy import func, select
@@ -44,6 +45,7 @@ async def create(
 
     db_item = models.Filament(
         name=name,
+        registered=datetime.utcnow().replace(microsecond=0),
         vendor=vendor_item,
         material=material,
         price=price,