chore: Fix Anki 23.12 incompatibility (#830)

fix: Don't start background thread from background thread

Co-authored-by: Heitor Carvalho <[email protected]>

ankihub/gui/deck_updater.py

@@ -49,7 +49,7 @@ def update_decks_and_media(
         # The media sync should be started after the deck updates are imported,
         # because the import can add new media references to notes.
         if start_media_sync:
-            media_sync.start_media_download()
+            aqt.mw.taskman.run_on_main(media_sync.start_media_download)
 
         LOGGER.info("Finished updating decks")
         return self._import_results