Fix detrend transforms to handle integer timestamp

[d-a-bunin]

Before submitting (must do checklist)

• Did you read the contribution guide?
• Did you update the docs? We use Numpy format for all the methods and classes.
• Did you write any new necessary tests?
• Did you update the CHANGELOG?

Proposed Changes

Look #155.

Closing issues

Closes #155.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

❗ No coverage uploaded for pull request base (unaligned-data@6e14ccf). Click here to learn what that means.

Additional details and impacted files

@@                Coverage Diff                @@
##             unaligned-data     #163   +/-   ##
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  Coverage                  ?   89.26%           
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  Files                     ?      195           
  Lines                     ?    12742           
  Branches                  ?        0           
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  Hits                      ?    11374           
  Misses                    ?     1368           
  Partials                  ?        0           

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