add deprecation warning to resample function

[alisnwu]

closes #139

as per discussion in #180 and #207 warnings.warn passes pytest under python 3.13, 3.12, 3.11

@sbillinge ready for review

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (891d774) to head (784bc65).
Report is 2 commits behind head on main.

Additional details and impacted files

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  Coverage   100.00%   100.00%           
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  Files            8         8           
  Lines          362       362           
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  Hits           362       362           

[sbillinge]

Ah, I see, there was a new PR. Ok, np.