add kwargs to _warnings.py

[miltoncamacho]

Changes proposed in this pull request

add kwargs to the fmriprep _warnings.py script to handle new version of matplotlib warnings

closes #3478

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[codecov]

Codecov Report

Attention: Patch coverage is 40.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 73.49%. Comparing base (adf472c) to head (09da4e8).

Files with missing lines	Patch %	Lines
fmriprep/_warnings.py	40.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3483      +/-   ##
==========================================
- Coverage   73.52%   73.49%   -0.04%     
==========================================
  Files          60       60              
  Lines        4570     4572       +2     
  Branches      583      584       +1     
==========================================
  Hits         3360     3360              
- Misses       1083     1084       +1     
- Partials      127      128       +1     

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[mgxd]

Thanks for the PR! Ultimately, we will want to revisit (or altogether remove) our _warnings module, as we are now losing functionality.