rf(py314): Replace deprecated pkgutil.find_loader

[effigies]

This PR removes pkgutil.find_loader() and replaces it with importlib.util.find_spec(). find_loader was deprecated in Python 3.12 and will be removed in 3.14. find_spec has been present since Python 3.4.

Both functions return None if the module loader cannot be found. For its use in this project, this is sufficient and no translation of the return value is needed.

[welcome]

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 28.13%. Comparing base (2967323) to head (9f48b2e).

Files with missing lines	Patch %	Lines
qsiprep/cli/parser.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #828   +/-   ##
=======================================
  Coverage   28.13%   28.13%           
=======================================
  Files          69       69           
  Lines       10080    10080           
  Branches     1107     1106    -1     
=======================================
  Hits         2836     2836           
  Misses       7146     7146           
  Partials       98       98           

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[mattcieslak]

Thank you @effigies!!