Fix rest periods

[rouzbeh]

The current logic can end up classifying a long period of activity as the main rest period.

[codecov]

Codecov Report

Merging #32 (8f6fa00) into main (a453c4d) will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##             main      #32   +/-   ##
=======================================
  Coverage   47.11%   47.11%           
=======================================
  Files          91       91           
  Lines        7749     7749           
  Branches     1481     1481           
=======================================
  Hits         3651     3651           
  Misses       4027     4027           
  Partials       71       71           

Impacted Files	Coverage Δ
src/biopsykit/signals/imu/rest_periods.py	20.96% <0.00%> (ø)

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