baseline exclude= specifications complain if units are used

[teuben]

Describe the bug
The example for baseline subtraction claim we can use units in the exclude=, but it fails .

How to Reproduce

In the FS notebook I used

  exclude = [(-1500*kms,-400*kms),(-200*kms,50*kms),(600*kms,2200*kms)]

which caused the error

  ...
  File ~/GBT/dysh/src/dysh/spectra/core.py:126 in exclude_to_region
     if len(np.shape(exclude[0])) == 0:

   File ~/GBT/anaconda3/lib/python3.11/site-packages/numpy/core/fromnumeric.py:2024 in shape
     result = asarray(a).shape

   File ~/GBT/anaconda3/lib/python3.11/site-packages/astropy/units/quantity.py:1352 in __float__
     raise TypeError(

 TypeError: only dimensionless scalar quantities can be converted to Python scalars

Environment

• Dysh version
• Python version
• OS

[astrofle]

Just to be pedantic, the example notebook says explicitly: Right now, compound exclusions only work in channel space.