Don't WARN about git config returning 1

[jwodder]

Closes #27.

[codecov]

Codecov Report

Attention: 12 lines in your changes are missing coverage. Please review.

Comparison is base (c2dc0fe) 74.80% compared to head (31e4a45) 74.60%.
Report is 1 commits behind head on main.

Files	Patch %	Lines
src/backups2datalad/aioutil.py	7.69%	11 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #29      +/-   ##
==========================================
- Coverage   74.80%   74.60%   -0.21%     
==========================================
  Files          17       17              
  Lines        2731     2733       +2     
  Branches      596      597       +1     
==========================================
- Hits         2043     2039       -4     
- Misses        520      526       +6     
  Partials      168      168              

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[jwodder]

@yarikoptic Ping.

[yarikoptic]

Thank you!