Intermittent online goes failures.

[nabobalis]

Sometimes a selection of the goes tests fail:

============================================================================= short test summary info ==============================================================================
FAILED ../../.tox/py38-online/lib/python3.8/site-packages/sunkit_instruments/goes_xrs/tests/test_goes_xrs.py::test_calc_rad_loss_nokwags - ValueError: ['http://hesperia.gsfc.nas...
FAILED ../../.tox/py38-online/lib/python3.8/site-packages/sunkit_instruments/goes_xrs/tests/test_goes_xrs.py::test_calc_rad_loss_obstime - ValueError: ['http://hesperia.gsfc.nas...
========================================================= 2 failed, 18 passed, 205 warnings, 5 rerun in 397.99s (0:06:37) ==========================================================

What ones or when they fail seems to be random(?!) but they all use the data manager in some form.