refactor: LEAP-1308: REVERT Remove Stale Feature Flag - ff_back_dev_3865_filters_anno_171222_short

[luarmr]

Reverts #6744

LSE selenium test are failing, just in case creating this.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 76.70%. Comparing base (498433f) to head (ec85d1b).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #6753   +/-   ##
========================================
  Coverage    76.70%   76.70%           
========================================
  Files          170      170           
  Lines        13919    13919           
========================================
+ Hits         10676    10677    +1     
+ Misses        3243     3242    -1     

Flag	Coverage Δ
pytests	76.70% <ø> (+<0.01%)	⬆️

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