ci: Upgrade fern version

[robot-ci-heartex]

Hi @robot-ci-heartex!

This PR was automaticaly generated via Follow Merge.
Please ensure that all linked upstream Pull Requests are merged before proceeding with this one.

• ci: Upgrade fern version label-studio-sdk#375 linked by Workflow Run

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 76.78%. Comparing base (6da49c1) to head (755575f).
Report is 4 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #6815   +/-   ##
========================================
  Coverage    76.78%   76.78%           
========================================
  Files          171      171           
  Lines        14023    14023           
========================================
  Hits         10767    10767           
  Misses        3256     3256           

Flag	Coverage Δ
pytests	76.78% <ø> (ø)

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