fix: change task queue from NET to LIMIT

To get the URLs for images from a source we use a request similar to indexing the source.

tubesync/sync/tasks.py

@@ -706,7 +706,7 @@ def check_source_directory_exists(source_id):
         source.make_directory()
 
 
-@dynamic_retry(db_task, delay=10, priority=90, retries=15, queue=Val(TaskQueue.NET))
+@dynamic_retry(db_task, delay=10, priority=90, retries=15, queue=Val(TaskQueue.LIMIT))
 def download_source_images(source_id):
     '''
         Downloads an image and save it as a local thumbnail attached to a