Add logging calls and fix a couple of dask-related issues

[astrofrog]

@keflavich - this might help understand what reproject is doing. Probably should document this, need to do:

import logging
logging.basicConfig(level=logging.INFO)

to see any messages

[codecov]

Codecov Report

Attention: Patch coverage is 82.92683% with 7 lines in your changes missing coverage. Please review.

Project coverage is 91.26%. Comparing base (8014869) to head (2ab5757).
Report is 49 commits behind head on main.

Files with missing lines	Patch %	Lines
reproject/mosaicking/coadd.py	71.42%	6 Missing ⚠️
reproject/common.py	95.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #450      +/-   ##
==========================================
- Coverage   91.52%   91.26%   -0.27%     
==========================================
  Files          25       25              
  Lines        1027     1065      +38     
==========================================
+ Hits          940      972      +32     
- Misses         87       93       +6     

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[astrofrog]

@Cadair - how do you feel about this in principle? Any downsides?