Log a warning if a cached file's length cannot be verified

[snbianco]

See this discussion.

Rather than raise an error when a cached file's length cannot be verified, warn the user and re-download the file. This is needed for certain files in the MAST Archive that are generated dynamically and don't include a Content-Length header in their response at this time.

My understanding was that this could not be tested in test_query.py, but I did add a case in the MAST module tests.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.

Project coverage is 69.36%. Comparing base (4c2caa2) to head (4ed16e4).
Report is 168 commits behind head on main.

Files with missing lines	Patch %	Lines
astroquery/query.py	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3290      +/-   ##
==========================================
- Coverage   69.37%   69.36%   -0.02%     
==========================================
  Files         232      232              
  Lines       19689    19692       +3     
==========================================
  Hits        13659    13659              
- Misses       6030     6033       +3     

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[keflavich]

Looks good, thanks for implementing this (and the test!)

[bsipocz]

Thanks!