AttributeError: 'NoneType' object has no attribute 'delay'

Sentry Issue: GWCELERY-TN

AttributeError: 'NoneType' object has no attribute 'delay'
  File "gwcelery/tasks/external_triggers.py", line 132, in handle_grb_gcn
    external_skymaps.get_upload_external_skymap(graceid).delay()

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information